Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Security.Permissions.EnvironmentPermission, mscorlib, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.
I have been working on an AppDomain sandbox and was plagued with permission failures where there should be none, namely at the constructor of a type being activated with CreateInstanceFrom, which should allow an Unrestricted permission assert in the constructor, even in a restricted AppDomain.
Ultimately I set exceptions to break and drilled down into the failed permission assert and noticed Read="AutoFakeEnabled".
This smelled like Typemock getting in my way and sure enough disabling Typemock resolved the issue.
I am not going to quantify the lost time, it would be embarassing, but it does raise some usability issues regarding Typemock.