I just wanted to run an assembly from a network drive and this assembly was failing because network drives are untrusted because of CAS (Code Access Security).

If you are in a similar permission and want to give a network drive full trust you can use the caspol.exe tool located in the .NET Framework directory. 

The command you should use is something like the following (where U is the drive I am trusting):

c:\>caspol -q -machine -addgroup 1 -url file://U/* FullTrust -name "User Drive"