I have a friend (really!) who is having a problem in Excel. She starts to
highlight cells (by clicking and dragging the mouse). But then selecting gets
"stuck" and the mouse just stays in the highlighting mode--without clicking
and dragging. Wherever she moves, the highlighted selection continues to
highlight or de-highlight. The keyboard doesn't work (i.e. up/down arrows,
ALT+f, etc.). If you try to click on a menu choice, nothing happens. We
basically CTRLALTDEL (which does work on the keyboard) and end the task.

Today everything was fine for a little while and then this started happening
again--so it's intermittent. :(

The file does not present the same problem on another computer.

Next time it happens I'm going to have her check and make sure she is not in
EXT mode by mistake. But otherwise I have no ideas. Does anyone?
TIA