Win 7 Pro.

I tried to use Windows DVD Maker to burn movies (WMV format) to a DVD to play on my TV.
I've had success doing this in the past (as recently as 2 weeks ago), but now I'm encountering a problem.

I can add the video files to the DVD maker with no problem. When I get to the screen where I start to burn the DVD, the program indicates that is encoding the files (a fairly slow process, which appears to be going OK), but then the progress indicator jumps to the end, the disk ejects, and a message appears stating that there was an error when attempting to create the DVD.

I verified that the DVD burner is fine by using BurnAware to burn a DVD, and by trying my second DVD burner. Both work fine with BurnAware, neither work with DVD maker.

I went to Programs and Features in Control Panel, Turn Windows features on or off, and turned off DVD maker. Then I turned it back on, hoping that it would repair itself, but it still gives me the error.

I should note that I've been leaving Windows Media Center turned off, but DVD maker worked fine before with Media Center off, so I don't think that makes a difference here.

Any ideas why this is happening?