.mkv file wreaked havoc on my PC

I downloaded an .mkv file not knowing that it would cause me so many problems...now I wish I had known. The file wouldn't play, and then whenever I tried to bring up my desktop (which is where the file was downloaded to) I kept getting "windows explorer has stopped working) over and over again. Other files would work just fine. So after some restarts and searches for ways to delete the file, it mysteriously disappeared from my desktop...I don't know how, but it's no longer there.

I'm in a long distance relationship, and I use Skype daily for voice calls. When my boyfriend tried to call me on Skype after this started happening, as soon as we'd connect on voice Skype would shut down...that never happened before. I haven't tried any other programs to see if they would work because I'm afraid to make a bad situation worse.

Does anyone know what I can do to fix any of this short of reformatting my PC?

See if you have a System Restore point available that dates just prior to downloading the file. If so, use it. If that doesn't work, do you have a backup image of an appropriate date?

Thanks :)

Wound up doing a reformat and clean install anyway. I did try a system restore as advised in here...actually I did that twice and it didn't work. But everything's fine now since I reformatted and reinstalled Windows.

Thanks again, much appreciated!!