Can't create new features without corrupting shapefiles

I am working on editing/creating some fairly simple shapefiles in ArcView 9.3.

This morning, I had a series of crashes while trying to digitize a polygon in an edit session. That shapefile seems to have gotten corrupted and I can't open it ("Error opening feature class--the number of shapes does not match the number of table records").

Because the crash happened during an edit session, I wasn't too surprised or worried that the shapefile was corrupted. Rather than wrestling with trying to fix the corrupted shapefile, I created a new shapefile with ArcToolbox and started over. I opened an edit session, digitized my polygons into the new shapefile, saved the edits, and stopped editing. All seemed to be fine.

Now that file won't open, either, for the same reason.

Now I'm going back to some work I did earlier, and I notice that every file where I've edited geometry--points or polygons--in the last couple of hours seems to have the same problem. This seems to be a systematic problem with creating new features in an edit session on my computer.

to test this, I just created a test file, opened an edit session, sketched a couple of squares, saved the edits, and tried to add the new shapefile to a project, and I get the same error.

There seem to be a lot of suggestions on the forums about fixing corrupted shapefiles. However, I seem to have a bigger problem: If I want to edit, my computer has become unable to create ANYTHING BUT corrupted files. Has anyone ever heard of this happening?

Thanks,
Geoff