Permanent crush

[kartus]

Hello all.
I reinstalled my OS yesterday, and since than my BS player crushes almost every time I try to open files (any kind, avi, mp3, mkv and etc). Sometimes it doesn't and crushes 15-20 seconds later.
I'm using 64 bit windows 7.
I'm using the exactly same windows as the one I removed (the same USB, that hasn't been used since the previous reinstall). First I tried with the same install file I had from before (v2.71), than I installed the latest free version from BS players website. I installed all codecs. I even tried a pirately activated version. All make the same problem.
PS. I don't have an antivirus program and my firewall/auto updates are off, so they are not the issue.
Thank you in advance, best regards.