Erros when saving workbook with different name
 

Hello,
I am using Excel 2007 SP2 and have a Workbook that I have been saving and
renaming by increasing the version number in the filename. Currently it's on
V17 but suddenly every time I save it with a different name, the calculated
fields all turn to N/A. If I simply save it without renaming it everything is
fine.
I'm worried that there is corruption somewhere but not sure what to look for.
Another thing that happens is that I can no longer email it without the N/A
problem appearing but I can save it onto a memory stick and copy it to
another computer.
There was only one macro and I have deleted it but I still have the problem
.. Has anyone experienced this?
Thanks!