Goto ToolsAutocorrect options...

scroll down the list, odds are there is an entry for ACN that gets changed
to CAN. delete it.

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HTH

Bob Phillips

(replace somewhere in email address with gmail if mailing direct)

"jk" wrote in message
...
I have a problem in my workbook that the cells will not accept the three
text digits of ACN but instead changes it to CAN.What could cause this to
happen?