worked on a project which is about an hour long. Using a/b eding...I added transitions,music,sound effects, etc. Everything was going great. I could watch on my tv as I went, etc. Opened the project up last night...I could see parts of it on the tv, but then would go black..seemed to go black when there would be an edit...could still hear audio thru tv...but if I drag the mouse across the timeline I can see everything fine on tv...Could I have accidently changed a setting before I closed Premiere that is causing this? Any suggestions to get me back up and running as I was 2 days ago? Pleeeease helllp!
You may have deleted (quite by accident) all the preview files for your project. Depending on the settings you chose for all the temporary files, directories like C:windowstemp will get cleared when you re-boot.
It sounds like you can see everything when you scrub the timeline (ALT key + drag the timeline cursor), so I doubt you've lost any of your project.
Another possibility could be that your desktop display resolution and color depth may have changed, that can impact the ability of your video card to update the playback window realtime.
With my Pinnacle Pro One card it's a little trickier . . . the card has a Video Renderer on it that looks to Windows like another VGA adapter. If the Display Properties setting "Extend my Windows desktop onto this monitor" is not checked/selected then Premiere won't update the contents of the Program window (the Source window will update/play just fine).