It could be that Avast is false positively flagging that file as infected( if it never happens before) patches in games etc are likely to be flag as virus by most antivirus.
I would just submit that file for an online check to make sure. It's also possible that the file is infected by a file infector though not likely if you're not getting any errors when running other programs.
http://virusscan.





by: warturtlePosted on 2009-05-01 at 04:35:06ID: 24278159
I would suggest that you download MalwareBytes Anti-malware from www.malwarebytes.org, and do a full scan with that (in safe mode, if possible). Its like a supplement to existing antivirus and is specialised for treating spyware. Nothing to worry about.