Infected file...cannot clean, delete or quarantine...

I have McAfee on my computer and have it scheduled to scan for viruses on my computer every Friday afternoon.  I just got home from work and it had found an infected file.  It says the file cannot be quarantined, please clean or delete the file.  When I try to clean it it says the file cannot be cleaned.  When I try to delete it it says it cannot be deleted.  What do I do???  The only other option is to just close out the program.

Thanks!
Kristen