FAQ: Access Denied when signing an assembly
Q: When I try to sign an assembly I get an access denied error. What is going on?
A: By default you can not sign an assembly unless you have administrative privileges. This is due to security set on the key(s) used for signing. To enable your account for signing assembly you will need to modify the NTFS security on the folder %ALLUSERS%Application DataMicrosoftCryptoRSAMachineKeys to give your user account (or better yet a group in which your account is a member of) full control. You will need read & execute, list and modify rights. You can then sign assemblies without administrative privileges.