This is the error that pops up after I install the game and try to play it. Already tried re installing, uninstalling and then installing again and same thing happens.

http://imageshack.us/photo/my-images/829/errorqa.jpg/

Uploaded with http://imageshack.us

Some anti-virus software thinks FalloutNV.exe is a virus. Try going to your anti-virus software exception file and add FalloutNV.exe to it. (Or unquarantine it if that's the case. Some anti-virus software doesn't always tell you if it thinks it found a problem.)