I have a function that helps check for duplicate records. It seems to work with American Settings but does not work with UK settings. Is there a difference in double quotes or something.

Here is the function:

CheckNullString (Incoming as Variant) As String

If IsNull(Incoming) = True Then
CheckNullString = ""
Else
CheckNullString = Incoming
End If
End Function

Any help would be greatly appreciated.

Sometimes checking the length of a string works better than checking for null values. It's easy to try:

If len(Incoming) = 0 then 'nothing there
CheckNullString = ""
Else
CheckNullString = Incoming
End If