This is due to a recent Windows Update. Please see the ANNOUNCEMENT at the top of this forum's main page for more detail.
This is that ANNOUNCEMENT:
ANNOUNCEMENT: Windows Update Causes Half of Display to Be Blacked Out
MicroSoft has issued an Update for Windows, that is causing problems with Displays. The following is from Talbot McInnis, who tracked down this problem, and offers a fix:
"MS bulliten MS13-057. Specifically, on XP kb2834904 and on windows 7 kb2803821 is causing a problem
For us, it occurs when decoding WMV9 files. Not all uses of WMV decoding are affected, but I confirmed that when connecting the WMV decode DLL to a sample grabber for RGB32 video, the frames arrive black on top, so that points directly to decoding internals of the WMV Decode dll.
You can uninstall these windows updates to resolve your problem."
There are several threads on the problem that this Update is causing on the PrE and PrPro Forums, so one can get more details. So far, there is not another fix from either MS, or Adobe.
Also, see this Adobe KB Article: http://helpx.adobe.com/premiere-pro/kb/wmv-files-corrupted-import-or.h tml
thanks – the uninstall worked.
Great news! That Windows Update has bitten many folk, myself included.
Last week, an Adobe engineer posted that MS was working on a fix, but I have not heard how that is going - hopefully soon.
Good luck to us all,
Two key points that are included in the many threads that have appeared here on the topic include:
For now, setting up Windows Updates requiring notification and your approval for any downloading and installing of updates (oldevhs).
If you do catch the offending Windows Update kb in Important Updates, right click it and select Hide. That is supposed to keep it gone (nealeh).
So far, that offending Update has not shown up again, and I have been notified of two sets of Updates, after the batch, that included that one.