Strange calculation issues

[Philip Trick]

Occasionally my coworkers and I encounter an issue where after making a
change to fairly large spreadsheets, we'll do a recalc (CTRL+ALT+F9 calc) and
nothing will recalc. We frequently have to do a Find and Replace "=" with "="
in order to get the calculations to update.

We typically turn the Excel calculation to manual due to the size of our
spreadsheets and rely upon CTRL+ALT+F9 or SHIFT+F9 (for a specific sheet) to
calculate when necessary, but in some cases calculations stop occurring until
we close Excel and completely reopen it (or use the Find and Replace method
mentioned above). CTRL+SHIFT+ALT+F9 locks Excel up when this occurs, with a
never ending "0% Calculated" until Excel bombs with an application error.

Any suggestions?

 

[PPE]

I am having similar problems with a Circular Reference which only occurs when
I copy a sheet to a new sheet. If I save the workbook under a new name the
calculation takes place without any problem. I'm still using Excel 97, so
maybe this has been fixed in later updates. I'm unable to get any window in
which to post this question, maybe you can help me with that too. When I
click on "New" & "Question" nothing happpens! Any help would be greatly
appreciated.