Try this.

Select the cells.

Edit>Replace

What:  =

With:  =

Replace all.

This is same as  F2 and Enter on each cell.

Gord Dibben  MS Excel MVP

Here's my standard checklist:
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     Cells not calculating (correctly)
     Niek Otten, March 31, 2006

     Most frequent causes:

     1.       Calculation is set to Automatic. This often happens unintentionally, for example by opening another workbook first.
     Calculation is an Excel-wide setting; the first workbook opened determines the calculation mode, which then applies to all
open workbooks and workbooks that are opened later in that instance of Excel. It can be changed manually (again, for all open
workbooks):
     Tools>Options>Calculation tab, check Automatic.
     2.       There are User Defined Functions (UDFs) which access cells directly from within the function, that is, not via the
argument list. Then Excel is not aware of the need of recalculation if the precedent cell changes. You can include
Application.Volatile in the function, but there is no guarantee this will always calculate cells in the correct sequence in all
(future) versions of Excel. It also causes the calling cells (and dependents) to always be recalculated, even if not necessary.
Really the best way is to include all precedent cells in the argument list.
     3.       You see the formulas in the cell, not the answers. Two options: a. Tools>Options>View, Formulas is checked (you may
accidentally have hit the shortcut key: CTRL+`), b. the cell was formatted as text before you entered the formula. Format as
General and re- enter (F2, ENTER). If it's about many formulas, select them, Find and replace "=" by "=". That's more or less the
same as re-entering them.
     4.       Excel version 5.0a (yes, very, very old!) has serious recalculation bugs, Excel 97 absolutely needs Service Pack 2
(SP2) to calculate correctly.
     5.       Very, very rarely, Excel's dependency tree gets messed up. One way to rebuild it is to find and replace all "=" by
"=", for all sheets (for Excel, this is like re-entering all formulas). Later versions of Excel rebuild by pressing
CTRL+ALT+SHIFT+F9
     6.       For many calculation secrets, visit Charles William's site:
     www.decisionmodels.com
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