Just had an interesting problem with a customer. He reported that a macro
wouldn't run. When I debugged, I found that a macro statement that counts
the columns in the used range was returning an overflow error. And another
statement that counted the rows in the used range also reported an overflow
error. The used range was small, A1:V195. I suggested he upgrade his copy
to insure he had the latest updates. He tried. However his installation
key, which came from a friend, would not allow him to upgraded - the key was
"over used".

It appears that when an installation key is over used that Microsoft is
turning off some of the features in VBA. I didn't see what message he got
when he started Excel, so I don't know if he got any warnings. Obviously he
didn't get any that made him think Excel and addins wouldn't work.

Bob Flanagan
Macro Systems
http://www.add-ins.com
Productivity add-ins and downloadable books on VB macros for Excel