I've moved this into the Security Awareness section (Home User Assistance) since this is to do with malware detection.
... most anti-virus programs detected that particular file as a trojan but it is in fact, not one
You sure it's not a Trojan? Go into Security Center and select Navigation. There should be a heading there for Quarantined and Trusted items. Go into it, select Quarantined Items. You can choose to restore it, but it's probably going to be detected and quarantined again the first time you run a scan. I would advise you send the file to McAfee (there's an option for that) so they can have a look at it.