You could do this with a workbook_change event. right click sheet tabview
codeleft window select worksheetright window select changewrite your
code.

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Don Guillett
SalesAid Software

"HuckinD" wrote in message
...
I have madesome tests in excel for my students. Is there anyway of
locking
cells down so that once they have entred an answer into one of the cells,
it
locks it in place preventing the answer from being changed