Just wanted to add that I had the same problem today and it was the PCAnywhere host running in the background that caused this error.

Sure enough, running an ATI Rage video card. I turned off shading and have not had a problem. Thanks for the help. Kevin

I tried saving a file which was originally created in Version 7 and get an error "Program Error Mill9.exe has generated errors and will be closed by windows ...." It only gives this error when surfaces are shown on the current level. I can delete the surfaces and it will save. I can switch to another level and it will save. I am running Win2000 OS and even tried exporting the file in IGES format and then importing it back into V9 with no luck. Anyone know what is going on?