For our invoicing we use the same worksheet every time, we just type in the
new information, print the invoice off and so on.  I came back into work
today and now when I type a certain word in any cell, as soon as I tab out of
that cell another word appears.  I cannot figure out why this is happening,
and it only happens when I type in one particular word, any other word is
fine.  

I hope I have made sense to someone out there that can help me.

Thank you