Option Explicit
Sub Essai()
If ActiveSheet.Name <> "TABLEAU ACOMPTE" Then Exit Sub
Dim n&: n = Cells(Rows.Count, 5).End(3).Row: If n = 1 Then Exit Sub
Dim cel As Range, i&: Application.ScreenUpdating = 0
For i = 2 To n
With Cells(i, 5)
Set cel = _
Worksheets("SYNTHESE PRR").Columns(5).Find(.Value, , -4163, 1, 1)
If Not cel Is Nothing Then .Offset(, 1) = Date
End With
Next i
End Sub