I am working in Excel 2007, although I don't think the problem is specific to
this. I have a workbook with about a 100 worksheets and 10's of thousands of
formulas. Basically, most but not all of the formulas are not calculating on
their own. I believe I have fixed this in the short term by using the
following sledgehammer when I am done with each worksheet.

Cells.Select
Cells.Replace What:="=", Replacement:="=", LookAt:=xlPart, _
SearchOrder:=xlByRows, MatchCase:=False, SearchFormat:=False, _
ReplaceFormat:=False

This really slows things down. Is there a more elegant way to do this
either with macros, computer settings, Excel settings, or something else?
Eventually I will work to reduce the number of equations, but can't do this
in the near term. Thanks in advance.