My dvd drive isn’t working. If I try to play a DVD, I get a message saying I need to insert a DVD. I think it thinks I’m trying to burn a DVD rather than watch one. All of my DVD playing programs crash when I open them. It was working fine this morning and I haven’t installed anything new or changed any settings since then. My laptop runs Vista.
Almost sounds like a software issue. Have you tried rebooting? How about a different DVD?
If that doesn’t work, try re-installing the DVD drivers. Go to Start->Control Panel->System->Device Manager. Find your DVD driver, right click, and uninstall. When that’s done, go to Action->Scan for hardware changes. Windows should download new drivers.
Windows might install the same (possibly corrupt) driver for the DVD player in that case. If it doesn’t work the first time around, get the make/model number of the DVD drive and check the manufacturer’s website for updated Vista drivers. Download those and use them to install the DVD player.
Also, some CD/DVD authoring programs don’t work well together. If the above doesn’t work, I’d recommend getting ride of any programs you don’t actually need.
Sound advice in general, although in this case it’s probably not a worry, since it was working 12 hours ago. But getting newer drivers is (almost) always a good plan.
Actually, now that I think about it, it’s possible that he did get updated drivers, and those had a problem. I also note that it’s Tuesday, which is Windows update day. Was there a media-related Vista update rolled out today?
Thank you for the replies. I cussed it out and went to bed. The next morning it was purring just fine. 
But I think I’ll bookmark this thread just in case.
(I’m pretty sure my roommate is tired of hearing me yell, “I’m the fucking administrator! Do what I fucking tell you!” at my laptop.)
“I know, but are you SURE???”
Oh, so you know my daily mantra?
(Fuck you Backup Exec! Cancel means Stop NOW, not say Cancel Pending for two fucking hours while the network slows to a crawl! Do NOT make me admin you!)