Stop Text Being Input
If you want to stop text being entered in a range you can use a Custom Data Validation formula.
Select the range and press in sequence, not held down, Alt a v v. This opens the Data Validation dialog.
From the Allow drop down select Custom (last entry).
In the Formula box enter the following formula
=NOT(ISTEXT(A2))
Replace A2 with the top left cell in your range. Make sure there are no $ signs in the reference.
Click OK.
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