I've reinstalled my Win-7 a couple of day ago (changed from 32 bits to 64) and now I have a strange problem with mkv files.
Before the update I used WDTV Live player to stream videos from the PC and everything worked flawlessly. Now the player fails to open mkv files from the PC through DLNA streaming. Other formats can still be played. The same mkv plays fine on both the PC and the WDTV if copied to a flashdrive. And the same file used to play on WDTV before Windows upgrade. So, the problem is not in broken mkv or network communication - something must be wrong with the codecs installed on the PC.
I'm using K-Lite codec pack, but the version I had before the upgrade was probably much older than the one I have now. Maybe some settings should be tweaked to make mkv-s play, but I have no idea what to check.
Any ideas on configuring the media server are appreciated.
Update: a detail which may help to solve the problem. When displaying the list of files on WDTV, the player shows only filename for mkv videos - no file size, time etc. So, the problem must be in the container, not in codecs. I also tried to encode the same file to mkv and mp4 using the same codec settings. mp4 is played fine while mkv still fails.