VLC on Windows 7 just started quitting when playing mkv files

[FrancisRumsky]

My VLC player running on Windows 7 home premium just stopped working with mkv files. It will play then for a short period and then cuts out. I can't forward past this spot either. It had been previously working fine and I tested a file that had previously worked and it does the same thing. I suspect that the recent Windows 7 upgrade might be the problem. I tried reinstalling VLC with the latest version and that didn't help. I ran it with messages active and verbosity set to 2 and found the following set of messages.

Any help would be greatly appreciated. Thanks Francis

mkv error: Dummy Element at unexpected position... corrupted file?
mkv error: Dummy element too large or misplaced at 204526904... skipping to next upper element
mkv error: This element is outside its known parent... upping level
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv debug: unknown (PN7libebml11EbmlElementE)
mkv warning: MKV/Ebml Parser: m_el[mi_level] == NULL
mkv warning: EOF
mkv warning: cannot get block EOF?
core debug: EOF reached
core debug: waiting decoder fifos to empty
core warning: picture is too late to be displayed (missing 12561 ms)
core warning: picture is too late to be displayed (missing 12576 ms)
core warning: picture is too late to be displayed (missing 12535 ms)
core warning: picture is too late to be displayed (missing 12368 ms)
core debug: finished input
core debug: removing module "avcodec"
avcodec debug: ffmpeg codec (H264 - MPEG-4 AVC (part 10)) stopped
core debug: killing decoder fourcc `h264', 0 PES in FIFO
core debug: saving a free vout
core debug: reusing provided vout
qt4 debug: Qt: Fullscreen state changed
core debug: removing module "faad"
core debug: killing decoder fourcc `mp4a', 0 PES in FIFO
core debug: removing module "samplerate"
core debug: removing module "scaletempo"
core debug: removing module "simple_channel_mixer"
directsound debug: closing audio device
core debug: removing module "float_mixer"
core debug: keeping audio output
core debug: removing module "mkv"
core debug: Program doesn't contain anymore ES
mkv debug: Stopping the UI Hook
core debug: removing module "record"
core debug: removing module "filesystem"
core debug: dead input
core debug: changing item without a request (current 2/3)
core debug: nothing to play
core debug: destroying useless vout
core debug: removing module "direct3d"
direct3d debug: Direct3D scene released successfully
qt4 debug: IM: Deleting the input
direct3d debug: Win32 Vout EventThread terminating
direct3d debug: Win32VoutCloseWindow
direct3d debug: WinProc WM_DESTROY
qt4 debug: releasing video...
qt4 debug: Video is not needed anymore
core debug: removing module "freetype"
core debug: removing module "yuvp"
core debug: removing module "swscale"

[Lotesdelere]

Reset the preferences:
https://wiki.videolan.org/VSG:ResetPrefs

[FrancisRumsky]

Thanks Lotesdelere but that didn't help. I reset the preferences after starting VLC, restarted and tested with an mkv file that had worked before this issue came up. It still stalled part-way in. I then used the link from the start menu of windows to reset preferences and delete the cache. SSDD. Any other ideas?