To run the installer, click the link below.
Run the installer


If the installer script fails with Server Error, make sure that ASP.NET version being used is 2.0 or above, not 1.1. You can find this information in the last line of the error page, for instance:
Version Information: Microsoft .NET Framework Version:1.1.4322.573; ASP.NET Version:1.1.4322.573
You can change it to 2.0 in ASP.NET properties of the virtual folder.

You should also make sure the physical path to the virtual folder in virtual directory properties does not contain trailing back-slash. The virtual folder must be configured as an application as well.

If the above does not help, refer WebMail Lite ASP.NET FAQ.