Small medium-sized businesses are our primary focus, particularly in warehouse distribution and retail sectors. We are a reseller and purchase directly from Sophos.
KerioConnect delivers easy-to-use and secure email, calendar, and collaboration tools compatible with Office, Apple, and ActiveSync. Cost-effective and flexible, it suits on-premise installations, especially for SMBs seeking privacy and security.
| Product | Mindshare (%) |
|---|---|
| KerioConnect | 2.8% |
| Mimecast Email and Collaboration Threat Protection | 14.5% |
| Microsoft Defender for Office 365 | 13.2% |
| Other | 69.5% |
| Type | Title | Date | |
|---|---|---|---|
| Category | Email Archiving | Jun 23, 2026 | Download |
| Product | Reviews, tips, and advice from real users | Jun 23, 2026 | Download |
| Comparison | KerioConnect vs Microsoft Defender for Office 365 | Jun 23, 2026 | Download |
| Comparison | KerioConnect vs Mimecast Advanced Email Security | Jun 23, 2026 | Download |
| Comparison | KerioConnect vs Barracuda Email Protection | Jun 23, 2026 | Download |
| Title | Rating | Mindshare | Recommending | |
|---|---|---|---|---|
| Google Workspace | 4.1 | N/A | 95% | 106 interviewsAdd to research |
| Mimecast Advanced Email Security | 4.0 | 14.5% | 92% | 42 interviewsAdd to research |
| Company Size | Count |
|---|---|
| Small Business | 7 |
| Midsize Enterprise | 1 |
| Company Size | Count |
|---|---|
| Small Business | 71 |
| Midsize Enterprise | 37 |
| Large Enterprise | 37 |
KerioConnect offers a comprehensive email server experience with minimal resource needs and effective spam filtering. Compatible across platforms, it supports Outlook, enabling organizations to manage corporate communications efficiently. Its ability to host multiple domains makes it suitable for sectors like warehouse distribution and retail, with installation options that enhance security and privacy. However, faster Outlook integration, improved MS Teams and CRM system integration, and AI functionalities are sought after by users. Some demand a cloud version, Linux support, and better documentation. Still, KerioConnect remains a reliable choice for those needing on-premise capabilities.
What are KerioConnect's Key Features?KerioConnect is widely utilized in SMBs across sectors like retail and warehouse distribution for its capability to handle multiple domains and integrate with Outlook for communication management. Resellers offer it as a dependable on-site email management solution, letting businesses maintain oversight and security control.
Southern Tier Brewing Company, Innotta, Baustoff + Metall, Hamifleurs, Chanson TV, Ryman Stationery
| Author info | Rating | Review Summary |
|---|---|---|
| Senior Systems Tech/Admin at Samco Software Inc. | 5.0 | I've used KerioConnect for over 15 years; it's stable, easy to set up, and ideal for small to medium businesses, offering solid features like VPN and spam filtering, though lacking full integration like Gmail or Office 365. |
| Senior Systems Tech/Admin at Samco Software Inc. | 5.0 | We use KerioConnect as our mail server for multiple domains and clients. It's easy to maintain and manage, with robust security features such as anti-spam and antivirus. Creating domains and performing backups and restores is straightforward. |
| Information Technology Specialista at REMING CONSULT a.s. | 4.0 | I use KerioConnect for emails, calendars, and collaboration tools. It integrates with Outlook and Apple devices, offering good spam filtering and antivirus. While suitable for smaller organizations, larger ones need better server capacity and integration with MS Teams. |
| Lead Hand - Print Department at a marketing services firm with 11-50 employees | 4.5 | I find KerioConnect to be a secure and private mail server option for on-premise installations, offering control over email access and flexibility. However, it lacks integration with services like Google Docs and Google Calendar, but remains reliable and cost-effective. |
| Vice President at a manufacturing company with 51-200 employees | 2.5 | I find this corporate email solution simple and stable, but it's basic, lacks CRM integration, and user documentation is terrible. It's slow, crashes easily, and recovery is difficult. The user experience is neglected, rating 5/10. |
| IT at a manufacturing company with 11-50 employees | 3.0 | We use KerioConnect as a mail server integrated with Outlook for calendaring tasks. However, it lacks smooth integration with Microsoft 365 applications, prompting us to consider switching to Microsoft Exchange for improved workflow efficiency. |
| Senior Technician at Computers At Work | 4.5 | I use Kerio Connect for email applications due to its ActiveSync support, simplicity, and stability. Though native Outlook integration could improve, it outperformed Microsoft Exchange with its ease of maintenance, affordability, and minimal system resource requirements. |
| Lead Hand - Print Department at a marketing services firm with 11-50 employees | 4.5 | I highly rate Kerio Connect for its security, flexibility, and ease of use, appreciating its stability and support. My main concern is the lack of redundancy and a native cloud version for better scalability. |
| Senior Systems Tech/Admin at Samco Software Inc. | 4.0 | No summary available |
| Director at a tech services company with 1-10 employees | 1.0 | I find Kerio Connect complex to set up and use, lacking a compelling use case, especially with Microsoft Exchange's prevalence. I wouldn't recommend it, preferring other solutions, and rated it poorly. |
Small medium-sized businesses are our primary focus, particularly in warehouse distribution and retail sectors. We are a reseller and purchase directly from Sophos.
KerioConnect is very easy and not as complicated as Sophos and other firewalls. Since it's proprietary, you connect it, do a site-to-site VPN, and you're ready. Everything comes with a yearly subscription, which includes firewalls, intrusion detection, IPS, and antivirus.
With KerioConnect, we have multiple domains served on one server.
Since KerioConnect is a setup and go solution, everything works on its own. The only administrative tasks required are keeping it up to date, monitoring security logs, and ensuring protection from brute force attacks.
We have been using the solution for more than 15 years.
The solution is very stable on its Linux platform.
Scaling is easy. We have licenses covered for 10,000, but we are currently using about 100 to 300 users.
I rarely encounter problems, but when I do, I post a support ticket on the website and they reply very quickly.
Positive
The setup process involves building a Linux server with the appropriate disk space, installing the RPM, and then it's ready to go. Setting up domains, users, and configuring spam filters is straightforward.
We are a reseller and purchase directly from Sophos.
The solution is beneficial for small and medium-sized businesses.
The pricing is very easy to understand. As a partner, we have a monitoring system that informs us when subscriptions expire, allowing us to handle renewals. The pricing is very competitive.
Servers that have apps integrate with Office 365 and Gmail. We cannot compete with them because they're fully integrated with their applications.
We remain a partner with Sophos and use XG S Firewalls without AWS implementation. We only use Sophos endpoint and Sophos Central.
We host some clients on-premise while others we host remotely. The VPN connection is easy and proprietary, so it's not open to any other VPN clients.
Communication with other mail servers is seamless. It can communicate with Gmail and Outlook without issues, provided the DNS settings are correct.
We monitor our servers and security logs, implementing GeoIP blocking. We frequently block China and India IPs due to brute force attacks on our servers.
We have extensive experience with KerioConnect. Backing up and maintaining it is straightforward compared to Microsoft Exchange, making it administrator-friendly.
On a scale of 1-10, this solution rates an 8.
We use the solution as our mail server and host it for other domains for our clients.
The solution is easy to maintain, unlike Exchange. It's easy to create multiple domains and back up and restore if needed. It also has good security features like anti-spam and antivirus.
I have been working with the product for eight years.
KerioConnect is stable as long as you use a strong password. It has its anti-virus,two-factor authentication, and anti-malware software.
We have companies with 50 domains and others with five. The mix is small and medium companies. We can accommodate up to 10,000 users, though we haven't utilized it to that extent yet. It can handle up to 10,000 users.
The tool's deployment is easy. You would need one person to handle the deployment. One person takes over me to maintain the solution while I am on vacation.
KerioConnect has a first-time cost and yearly subscription. It is not expensive.
The solution evolves with updates. New updates come out every four months. We can't compare it with other email servers like Outlook, which Microsoft maintains. KerioConnect is easy to maintain ourselves, unlike some other open-source options out there. Although KerioConnect is commercial, it is very easy to maintain.
We mainly use it for our accounting users who handle payroll, accounts payables, and accounts receivables. Most clients use it for emailing purposes and pay for our software through subscriptions.
I would recommend the tool to others since it is easy to maintain. I rate it a ten out of ten.
We use the solution for emails, calendars, and other collaboration tools. It is a self-serve application.
KerioConnect has integration with 365. We can use Outlook, which has its client and can be used with Apple devices. It integrates with the App Store and Microsoft Office. It has a smart router. The spam filtering and antivirus are good.
KerioConnect continues to improve with regular updates throughout the year. They must be added to the roadmap, which requires approval.
In larger organizations, the server's capabilities and the database need improvement. However, in smaller organizations, it works well. Better integration with MS Teams and AI features would be beneficial in the future. It should become more intuitive for the applications.
I have been using KerioConnect as a reseller for 15 years.
I rate the solution’s stability a nine out of ten.
KerioConnect is scalable. I have a couple of servers in one organization, so it is possible to configure it this way. We can have multiple servers within one organization and one domain. On these servers, users or services can be divided. Services like Jet, email, and login can be distributed across separate servers.
The tool is suitable for small and medium customers. I rate the solution’s scalability an eight out of ten.
Resellers provide the first level of support. After that, support is handled by distributors. The next level of support is from GFI. However, you can also request support directly from GFI. GFI has two levels of support. The first level is AI-based support using Atlas AI. The second level involves direct communication with SAP.
Positive
The initial setup of KerioConnect is very easy. Any admin, even with limited deployment experience, could do it. The setup is available in English and other languages, making it accessible. It only takes a few minutes to complete the database setup.
We have to set it up at the beginning. After that, you also have to set some antispam settings, create users, etc. It depends on the organization, but it's easy for the administration.
We can start on a Windows or Linux server. Preparing the machine takes some time. After the basic deployment, you must set up users and configure settings, which can be time-consuming. The ease of setup and the time required depend on your familiarity with the system.
I rate the initial setup as seven out of ten, where one is difficult and ten is easy.
The product is cheaper than Office 365.
I recommend KerioConnect to small organizations because it's easy to use and offers many features. However, I have other recommendations for enterprise solutions.
Overall, I rate the solution an eight out of ten.
KerioConnect is a mail server.
KerioConnect is a good and secure product. You can install it on-premise servers, making it more secure and private than other products.
The most valuable features are security and privacy because you installed it on your server, within your company premises, not in the cloud. You can control everything, and nobody has access to your email. It's very private and flexible to set up. You can set up different parameters in the area. The server is installed on your equipment or hardware inside your company.
Also, the product is cheap.
You cannot integrate with other services like Google Docs, Google Assistant, Google Calendar, etc.
I used KerioConnect for 5-7 years.
The product is stable and running 24/7. There is no problem, interruption, or crash. We run it under Windows Server 2012, but you can run it on Linux.
Scalability depends on the drive's storage capacity for storing all the emails. Kerio Connect works quickly and reliably. You don't need to set up a cluster of servers; just one server with enough space to store all the emails is sufficient
The product is suited for small businesses, providing excellent security and privacy. You have to keep the IT specialist in the company to keep running this product.
Customer support is reliable. It provides fast and excellent support.
Positive
The initial setup of KerioConnect depends on whether you're working with an IT professional. Setting up Google is easier, but KerioConnect needs direct access to all the server settings, which requires some IT knowledge. You have to be familiar with email technology, SMTP protocol, IMAP protocol, and other related aspects. There's a lot to configure, including port forwarding on your firewall, among other things. You have complete control over the setup and can tailor it to your needs. In contrast, setting up Google services is generally more straightforward.
To deploy KerioConnect, you must acquire some knowledge to set it up properly. It involves various technologies, such as firewall configurations, forwarding, and email protocols, to function effectively. You must manually configure the spam filters. Once correctly configured, KerioConnect offers various spam protection mechanisms for your email data. In terms of flexibility, it surpasses Google by a significant margin,
I deployed the product.
KerioConnect doesn't affect productivity. You can use its clients or the stock client for both Windows and Apple. Additionally, you can use the web interface and set up different email clients using the app. It's open and fast. It's reliable, typically responding within 50 seconds.
KerioConnect is cheaper than Google, Microsoft, or Zoho.
There are two kinds of maintenance. One is an on-time upgrade, which is very easy. The other is the log files and creating new rules for filters and security. It's more secure than Google.
In KerioConnect, you can access everything from security and filters to spam settings. You have set it up the way you want it. There's some knowledge required, but it works perfectly.
The interface is very clean, logical, and straightforward to understand. It's clear to know how to do it with the support and information provided on the website.
I recommend it for small businesses for privacy, security, and speed.
Overall, I rate the solution a nine out of ten.
It's a corporate email. All of our corporate emails go through it.
It's relatively simple to use.
The setup is pretty much straightforward.
It's very basic. It does the essential functions.
The search and archiving documentation capabilities need to be stronger. The user documentation is ridiculous.
The connectivity with CRM is a significant issue here. We don't have a great way of getting these emails into CRM except by copying and pasting text.
In terms of connecting, we really need to connect this to a CRM system and there doesn't seem to be an excellent way to do it. It's very much a standalone product and the documentation does not make this easy.
It is not unstable. However, for example, I recently personally crashed it due to the fact that I had too many items in my folder. It turns out there's a hard limit as to how many files you can have in a folder, and so I personally ended up crashing the system. The result was my IT person is still trying to recover most of my email, even though we've gone through all the backup procedures and all this other stuff over the years. Once I crashed it, getting back access to my old emails has proved to be very difficult. This recovery stuff turns out to be very, very difficult.
The IT guys love this thing, however, from the user perspective, it's slow when it's cumbersome. Their whole sales pitch and documentation are focused on IT people running this thing. They don't seem to be particularly focused on the user experience.
Also, this thing is not updated from a feature set perspective. It's virtually the same as it was when we bought it. Now, under the covers, they've made lots of changes. However, from a user perspective, it's still pretty much the same.
I’ve used the solution for about ten years.
The stability isn’t too bad. However, we have crashed the system and have had trouble recovering items again.
Fundamentally, this thing is very stable. It doesn't require a lot of care and feeding. However, it is very limited in what it does.
I don't really know much about scalability. Our user count has been relatively stable. It doesn't interface well with anything else that we found, people tend to use it as a file cabinet, and it does not seem to like that. It seems to make the searches incredibly slow.
In terms of the amount of data that it can hold, it doesn't seem to really be designed to hold too much data. We're a relatively small organization, and we seem to keep bumping up against all these constraints in terms of the size of user accounts.
Frankly, we shouldn't keep this stuff in email anyway; however, since we can't export it easily to anything else that's more like a corporate file cabinet, we end up trying to get it to do stuff that it obviously was not designed to do.
We have 50 to 60 people in our organization. We do not have plans to increase usage.
I don't deal with technical support directly. However, I would say my IT person puts it somewhere in the middle. My impression is that they answer narrow technical questions well; however, for more general kinds of things, they don't seem to be very helpful.
When I crashed the server, it took my IT person talking to them for over a week to figure out what I had done that crashed it since there was no documentation that anybody could see that said there was a hard limit as to how many files per folder.
Neutral
We used cc:Mail. Frankly, everybody around here just wishes they had cc:Mail back. However, cc:Mail became obsolete, and it had hard limits on how we could grow it.
It is easy to set up the solution. It’s not overly complex or difficult.
It must have taken about three or four months to deploy the solution. I can’t recall exactly. It was a long time since we set it up.
Very minimal maintenance is required.
The initial setup was handled in-house.
It's probably better than the alternatives. Does this make our business better? Does it give a competitive advantage? The answer is no. This is just a cost, it's not something that's driving our business forward; it's just foundational.
I was not involved in the evaluation process if there was one.
I’m a user. I’m not technical.
As far as I know, the solution is up to date, and we are using the latest version.
New users should evaluate the experience and evaluate the connectivity to other systems before signing up for this solution.
I am not in direct contact with them. However, what I get through my IT person is they are entirely focused. Their customer is the IT person, period. They don't think much about the end user. To me, when I compare it with other systems that I use Apple Mail or some other CRM-based emails, this is as basic as it gets. The connectivity is just a real issue. And they need to have user documentation beyond like, "This is how I turn the thing on." The user documentation is really terrible. We had to write our own user documentation and training material because their stuff was so bad.
I’d rate the solution five out of ten.
They have potential. However, there is a lot of room for improvement. Hopefully, they're going to fix a lot of it very soon.
We use the solution as a mail server. It connects with Outlook and is used for calendaring and similar tasks.
We are considering switching to Microsoft Exchange. One reason is that it doesn't improve our workflow and doesn't integrate well with Microsoft 365 applications.
I have been working with the product for three years.
The tool's stability is okay.
I rate KerioConnect's scalability a five out of ten.
KerioConnect's deployment is easy and takes 20 minutes to complete.
The solution's pricing depends on how long you plan to keep it because you pay on a per-year basis. You might have a one-time setup cost for something like Microsoft Exchange or a Linux mail server. I'd say this solution is expensive on a per-year basis, almost 2000-3000 dollars annually. It doesn't seem to pay off yet, so we're considering switching to another product.
I would advise others looking to use the solution to look twice before using it. Don't just jump into it. I wouldn't take my advice on how good it is because I don't know. I manage it, but I haven't set it up or anything like that. I rate the overall product a six out of ten.

I use Kerio Connect for email applications.
What I like most about Kerio Connect is that it supports ActiveSync, and that is its most critical feature. The solution is also a nice, simple, robust, and stable mail server. I also like that it doesn't require a lot of system resources to run because it's all integrated into itself, and it doesn't rely on any other technologies to function. We went from Exchange to Kerio Connect for those reasons.
Kerio Connect does as advertised, so there are no real issues with the product itself. It's developed regularly, so there are constant updates. Possibly, the support and development have lessened since they've sold the company, but as far as the product itself is concerned, there isn't anything that I would suggest needs improvement. If I'm being picky, Kerio Connect uses a proprietary, mappy atom for Outlook, and it would be nice if they used a native mappy connection instead, but that's the only additional feature that I would like to see in its next release. If they have native Outlook map integration, that would be great, but other than that, it's got all the functions that I think a mail server should have.
I've been working with Kerio Connect for ten years.
Kerio Connect is a stable solution.
Kerio Connect is a scalable solution. How easy it is to scale would depend on the degree you want it to scale. For our clientele, it's perfectly fine. If you have up to fifty users, it's fine. I haven't tried to scale it beyond that. I can't see any reason why it wouldn't accept more. I/O is the critical resource that it requires beyond that, so as long as you have fast drives, there's no reason why you couldn't go bigger in terms of scaling Kerio Connect. It supports a lot of features and clustering, and if we have a lot of users, it's fine.
We've worked with several solutions over the years, and we went with Kerio Connect because we weren't happy with Microsoft Exchange or Microsoft 365 at the time. We got more back from Microsoft Exchange, particularly in a host environment, but we found the on-premises version way too unwieldy for the number of clients, or the size of clients that we deal with. For example, the server and all the other infrastructure to make it function was way too complex and expensive, while Kerio Connect is simple and lightweight, and it does what you need.
Kerio Connect is also much easier to maintain and keep going, compared to Microsoft Exchange which was unwieldy. You have to update Microsoft Exchange, plus it has all these prerequisite requirements. We also tried SmarterMail, but we're stuck with Kerio Connect because it works.
The initial setup for Kerio Connect was very straightforward.
I evaluated Microsoft Exchange.
I use both Kerio Control and Kerio Connect.
Kerio Connect is deployed on-premises. It has a cloud version, but we use its on-premises version.
I'm giving Kerio Connect a high score, but it would depend on simple use cases and the number of clients you're using it for. For what we've used it for, it's a nine out of ten because it works.
We are running Kerio Connect as a mail server on a Windows Server system.
Kerio Connect is secure, flexible, and easy to control from the user interface. It has many security features able to be controlled from one place, such as anti-spam. I have found it very convenient. Additionally, you can analyze log files and share folders which is helpful.
The solution could improve the redundancy because we only have one copy of the Kerio Connect server on our hardware. The next step for us is to move to the cloud and if Kerio does not have a cloud version available they should release one.
Kerio Connect runs on Windows Servers which I do not like because it is not secure and reliable. I would prefer to run it under Linux.
I have been using Kerio Connect for approximately seven years.
I would recommend others to use a cloud-based or a SaaS solution.
The solution is highly stable and reliable.
The cloud version would have a better ability to scale which is available.
We have 30 people using this solution.
The technical support is amazing. You receive a fast response after you create a ticket and the agent are very technical and knowledgeable.
The initial installation is straightforward and takes approximately 10 minutes to configure the domain and accounts. It has a user-friendly interface design but you have to have some experience to start setting it up. The interface is clear, transparent, and made in a logical way. You can have access to the on-site Kerio Connect from outside the company through a website provided by Kerio to control all the settings and configuration.
I did the implementation myself.
The solution works well by itself, it does not require a lot of maintenance. We only have to manage the hard drives. I only analyze the security and spam logs on a daily basis to make some new rules if needed in order to protect ourselves from phishing emails and from spam that could overload our servers.
The price of Kerio Connect is better when comparing it to others solutions.
We evaluated Microsoft Office and Google's solutions but we found Kerio Connect suits us best.
I rate Kerio Connect a nine out of ten.
We primarily use the product as an integrated solution for our calendars and contacts and everything else. It's attached to our carrier operator.
It's a very healthy solution. It has a good survey or features that we like to use.
The user interface is good.
The implementation process isn't too complex.
We've been happy with the solution. It's worked for us so far so it's fine.
If they could integrate some sort of AI into the solution to make it more efficient, that would be interesting.
Most of our clients use Outlook and Kerio Connect. Occasionally, Kerio can be a bit slow. They could make it faster to get onto the web interface without so much load time. It's just slow with Outlook, however, for some reason.
We've been using the solution since the product's inception. It's been about 15 years or so.
As long as the operating is stable, the Kerio connect will be very stable as well, so we don't have any problem with it. There aren't bugs and glitches. It doesn't crash or freeze. I consider it reliable.
The solution can scale quite well. It can accommodate 10,000 depending on your hardware. It's quite robust.
It's a multi-domain solution. More than one company can be on the solution at one time.
We don't plan on increasing usage at this time.
The solution's implementation is not complex in any way. It's pretty straightforward. We're using Linux systems to install it, however, we stay away from Window's services. That's a personal preference thing on our end.
We tend to maintain the solution for our clients. We have one person who handles maintenance and she's knowledgeable in everything from hardware to software to the operating system.
We had help on the more technical details of the setup.
The pricing is about $3 per mailbox per month.
We have a mix of deployment models, beyond just the cloud.
If you're an admin, it's much preferable to use Kerio Connect because it's, easy to manage.
Overall, on a scale from one to ten, I'd rate the solution at and eight. There's no perfect system, however, this solution works quite well for us.
We have not used this solution on a business level, but we have had other clients who are using this solution.
We don't have uses for this solution, but some users have historically used it where they had onsite or on-premises email servers.
With the ubiquity of Microsoft Exchange, we don't see it being used very often.
I don't find it easy to use, but it might be because it is not my main technology.
It could be simpler to use and install, but I still wouldn't use it because there isn't a compelling use case.
I have been dealing with Kerio Connect for two years.
I can be deployed both on the cloud, and on-premise, it depends on what our clients use.
We have five customers who use this solution.
We have contacted technical support a handful of times and received some assistance.
We also use Microsoft Exchange.
In my opinion, I find the setup to be complex.
The number of people required to maintain this solution depends on the size of their team.
I don't particularly like this solution. I prefer Microsoft solutions. I am more comfortable using them. I have more experience.
I would not recommend this solution to others. I would not really use this solution, most of our clients use 365.
I would rate Kerio Connect a two out of ten.