I like the ease of login best in GroupWise. With the desktop client you can login to GroupWise independently of the PC login and it has Web Client that can be used if your prefer not to install the client or are using a PC that does not have the GroupWise Client installed. I also like its user proxy capabilities. I also like the level of security that it provides. Additionally, it comes with GroupWise Messenger for secure instant messaging to desktop or mobile devices. It integrates well with the email on your mobile devices and smart phones via GroupWise Mobile Services.
