If the string you’re looking for isn’t found you’ll get that error. The find function returns “Nothing” if nothing is found
Dim r As Range
Set r = Cells.find(What:=strCliBoa, After:=ActiveCell, LookIn:=xlFormulas, _
LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
MatchCase:=True, SearchFormat:=False)
If r Is Nothing Then
'handle error
Else
'fill in your code
End If