Backdoor.Graybird in Windows 7 Pro

How can I confirm whether I am infected by Backdoor.Graybird trojan in Windows 7 ?

I may have ran an executable prior to my installation of Norton Security on my new laptop.  A norton virus scan found an .exe file in one of my backups that it classified as Backdoor.Graybird.  When I click on their link for information on it (tech details, recommendations, and removal information) it does not mention windows 7. 

Yes, I have ran a full system scan on my laptop and it says no threats found.   If I already ran a suspect executable would a standard virus scan be able to see anything the virus may have changed such as registry keys?

Thanks.