Take a look at the event viewer of Windows. If there is no entry it is highly likely that any security software has blocked the file. Bit Defender is known to be aggressive on my trainers and it is also known to 'ignore' user settings, one of a few reasons why I recommend to switch to an alternatively AV.
//edit: You can also try to simple restart your computer if you haven't already.
[Edited by 0x90, 8/12/2014 4:46:32 AM]
Which AV do you recommend 0x90? I need to get something different myself. Saw some things about MS Security Essentials that turned me sour on that one. I also use MalwareBytes, but which AV do you like best?