[Windows 7] Windows Explorer keeps crashing/ restarting when attempting to transfer..

[Ultima]

.mkv files from my computer to [insert any smart phone/ tablet I own].

I am able to transfer .avi and music files without issue.

edit: As suggested, removing DivX Plus has allowed the transfer of .mkv files without issue. Would love someone to explain how that fixed it, but cheers!

[CTSNic]

I'd say it was the DivX Codec. But I do not understand why DivX Plus or Codecs would have any part of a file transfer. When trying open .mkv did DivX open or run in the background?

[Vargur]

I don't understand either. The closest resemblance of an issue would be if the mobile device would be in FAT32, and mkv files are usually over 4GB. That would not work at all.
Just use http://www.cccp-project.net for your codec needs.