Sub ForceCalcul()
Dim plage As Range, cel As Range
Application.ScreenUpdating = False
Application.EnableEvents = False
Application.Calculation = xlCalculationManual
On Error Resume Next
Set plage = ActiveSheet.UsedRange.SpecialCells(xlCellTypeFormulas)
For Each cel In plage
cel.Formula = cel.Formula & "+µµµ"
Next
plage.Replace "+µµµ", "", xlPart
Application.Calculation = xlCalculationAutomatic
Application.EnableEvents = True
End Sub