Trojan.Patchep!sys Removal Advice

Can someone please advise me as to how to manually remove the Trojan.Patchep!sys virus from my laptop? I am running Windows 7 Home Premium with the 64-bit operating system. According to a Norton full system scan the affected file is: C:\windows\system32\services.exe

 

I have a flash drive available for use during the removal process.

 

Thank you in advance for any help you can offer!