I used to get this quite a lot.

I was running Premiere Pro 1.5.1 and editing HDV material. Also, it turns out that another contributing factor is the Matrox RT.X100 card inside my editing rig.

Does any of this sound familiar?

If not then there is a Microsoft Windows update that is supposed to help these 'unknown erros' in Premiere. I can't remember the id of the patch buy it's there. I'm sure with some intelligent searching you can find it.

However, if that stuff above DOES sound familiar then I might be able to help.

All my (similar) problems went away when I purchased Cineform Aspect HD and installed it along with the following.

There is allegedly some kind of conflict betweenthe cineform stiff and the Matrix RT.X100 drivers. What you need to do is decide which mode you want to be in for that session and then either move the Matrox or the Cineform directory elsewhere, waya from the
Premiere Pro 1.5 -> Plug-ins -> en_US
directory. i.e. make sure you have one or the other tohand som only the one you want in that session actually get loaded when you start Premiere.

This is what cured it for me. I hope it helps.

Alan

__________________
I'm not young enough to know everything!