SUMMARY

If you are experiencing a session timeout instantly when logging into web mail, it is likely that the Web garden (maximum number of worker processes) setting for the MailEnable application pool is not set to 1.

RESOLUTION

Windows 2003 servers:

1. Open the IIS administration program: Control Panel->Administrative Tools->Internet Information Services (IIS) manager.
2. Expand the local computer branch, and the "Application Pools" branch.
3. Right click on the "MailEnableAppPool" icon and select "Properties" from the menu
4. Next navigate to the "Performance" tab.
5. Ensure the "Web garden" setting is set to 1.
6. Click "Apply" then "Ok" to close properties window.
7. Right click on "MailEnableAppPool" and select "Recycle".
8. Navigate to the Web mail URL and test.

Windows 2008 and later servers:

1. Open the IIS administration program: Control Panel->Administrative Tools->Internet Information Services (IIS) manager.
2. Expand the local computer branch and click on "Application Pools" icon.
3. In the "Application Pools" window right click on the "MailEnableAppPool" in the list of application pools and select "Advanced settings".
4. Scroll down to the "Process Model" section and ensure the "Maximum number of worker processes" is set to 1.
5. Click "Ok"  to close the window.
6. Right click on the "MailEnableAppPool" and select "Recycle".
7. Navigate to the Web mail URL and test.

MORE INFORMATION

Setting the timeout for web mail sessions: https://www.mailenable.com/kb/viewarticle.asp?&File=me020120.htm

Session Timeout Error when accessing web mail or web admin: https://www.mailenable.com/kb/viewarticle.asp?&File=me020150.htm

Web mail sessions timeout periodically on Windows 2003: https://www.mailenable.com/kb/viewarticle.asp?&File=me020257.htm

After a few minutes, Session Timeout errors occur when accessing web mail: https://www.mailenable.com/kb/viewarticle.asp?&File=me020258.htm