%windir%\Microsoft.NET\Framework\v7\aspnet_isapi.dllĪs you mentioned I check the 'Request Restrictions' - the checkbox is unchecked. NET AppPool' and the *rem handler is set to (this is similar to check if file exists). Make sure it's mapped correctly to aspnet_isapi.dll and under 'Request Restrictions' the checkbox called 'Invoke handler only if request is mapped to:' is UNCHECKED. Can you please look at the handler mappings for *.REM - specifically for the vdir or site where your remoting application reside?