Set-AuthenticodeSignature and Remote

I have a simple script that sits on Machine1.  The script pulls a certificate from the CurrentUser\My store for codesigning and passes it to the Set-AuthenticodeSignature command.   If I execute that script on Machine1 everything executes just fine.  It signs the target files with the correct certificate.

However if I log into Machine2 and create a New-PSSession with valid network credentials and try to execute that same script the Set-AuthenticodeSignature returns a status of "UnknownError"  Is there anything specific about using Set-AuthenticodeSignature that would not work calling it remote?

Any help would be appreciated.

--Brian