I'm getting "The previous session was terminated due to a timeout" message. Please help!

The typical reason of such error message thrown by WebMail Pro ASP.NET is unexpected loss of session data. By default, InProc session-state mode is used by .NET version of WebMail Pro. That means that session data are kept in web server memory.

If you experience random logouts, it might be helpful to switch session-state mode from InProc to StateServer. In this case, session state is stored in a separate process called the ASP.NET state service.

First of all, you should make sure that ASP.NET state service is running on the server used for the session store. ASP.NET state service is installed as a service when ASP.NET and the .NET Framework are installed. The ASP.Net state service is installed at the following location:

systemroot\Microsoft.NET\Framework\versionNumber\aspnet_state.exe

To configure WebMail Pro .NET to use StateServer mode, locate the following line of web.config file (the file is found under root directory of WebMail Pro):

<sessionState mode="InProc" stateConnectionString="tcpip=127.0.0.1:42424" sqlConnectionString="data source=127.0.0.1;Trusted_Connection=yes" cookieless="false" timeout="60"/>

The mode attribute should be set to StateServer, and the stateConnectionString attribute to tcpip=serverName:42424.

Alternately, you can make use of SQL Server Mode which assumes storing session data in SQL Server database.

You can find detailed information about different session-state modes in MSDN: ASP.NET Developer Center.