I did some more work and found a solution that works.

It runs a check on Cell E5, changes its value to 50 if it is greater then 50 and then shows a message box to the user stating a change was made.

Sub GreaterThenFifty() 'Name of macro
Dim WeekNumber As Double 'Use Double instead in case a half a week is used. Double allows decimal points and larger values to be entered then Integer
Dim WeekChange As Double 'Use Double instead in case a half a week is used. Double allows decimal points and larger values to be entered then Integer

WeekNumber = ActiveSheet.Range("E5").Value

If WeekNumber > 50 Then 'Check if WeekNumber is greater the 50
ActiveSheet.Range("E5").Value = 50 'Change Cell E5 to 50 if above statement is true
Msg = "Week Number is greater then 50. Changed to 50."
MsgBox Msg 'Inform the user of the change
End If

End Sub

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