'Session timed out or incorrect session ID' page in WebMail.

[admin]

This can be caused by a variety of reasons and usually can be solved by adjusting the WebMail settings. The first item to check is that the session time out value isn't too low, we recommend a minimum of 30 minutes. Also, it is possible that the user's IP is changing between requests, and so triggering a session security mechanism. This is particularly common with users behind proxies (such as AOL users) whos requests can get routed via different servers. The solution is to disable the option 'Restrict Session ID Access to the IP used During Login'.