I came recently across a strange error while trying to access my SAP Afaria 7 self-service portal. Suddenly I got a 403 error message.
The server was down for a few days as I did not have to use it. Maybe the shutdown of my VM didn`t work or Microsoft installed some patches, or something else. I took a look at the site configuration at IIS Admin and the connection string to the AD looked good. I reinstalled the self-service component, but this did not solve the issue. In IIS, there are ASP app pools, maybe something was wrong. Google pointed me to take a look at the ISAPI and CGI Restrictions located at the root of the web server. The ASP.NET for 64 bit was not allowed to be used (restriction).
I activated that one. Afterwards, all are allowed (32bit and 64 bit, for all version). To be on the safe side, I also run aspnet_regiis.exe –I from the installation directory of .NET v4 64bit.
Command: aspnet_regiis.exe –I
Now I was able to log on to SAP Afaria Self-Service Portal again!