>A customer has several DOS 2.5 programs written by me. In 2 of the programs, when he presses the UP ARROW key the field is filled with 666. I have replaced the exe file and the runtimes and the problem persists. In the other programs the UP ARROW key acts normally. Has anyone else experience this and if so is there a cure? Thanks.

Have you tried a different keyboard? Or, you can try my cheap keyboard fix:

- turn the keyboard upside down over a cloth, newspaper etc. then bang on the back of it so all the staples, paper clips, hairs, dead ants etc. fall out. Try not to be grossed out by what falls out.

- turn it right side up and hit all the Shift, Ctrl, Alt, and special Windows keys repeatedly, making sure they all seem to work freely. A lot of times I've seen one of these keys "stuck on" with strange results.