I am running the same OS & version. I get the same error. MMmmmmm
I had never tried to render to .wmv before. All else has worked fine for the last 2 years!
I have XP on an e-machine with Vegas and haven't had any problems rendering to the WMV templates in Vegas (versions 3 & 4). What version of WMP do you have, 8, 9? You might try reinstalling WMP to restore any missing files that Vegas is looking for. I'm using WMP-9 with no problems and very good quality. Hope that helps.
Randy
Is WMP-9 running better? there was some conversation a few months back and the guys would not download 9 because there were issues with it and you were unable to revert back to 8.
Love it! No problems and better quality. Everything I put up on our web site is -9 rendered using the 256K template (good for streaming). See examples at this address: http://www.cr-home-videos.com/. Click on sample videos and then your choice of video. All stream quick if you have cable or DSL. The JAWS show is less quality due to the source but all of the others show well even at that low bit rate. You can render at full screen also in -9 (change setting on the video tab) and the quality is as good as DVD. Hope this answers your question.
Randy