Function ChkMailExt(maildbpath As String) As String
 ' checks incoming string for .nsf extension, if exists, returns same string, otherwise it appends it to the end
 Dim nsfpos As Integer     ' position of .nsf in maildbpath
 
 On Error Goto FErrorHandler
 
 ' test for nothing
 If (maildbpath="") Then
  ChkMailExt = ""
  Exit Function
 End If
 nsfpos = Instr(1, maildbpath, ".nsf", 5)
 If Not (nsfpos>0) Then
  ' not found, add extension
  ChkMailExt = maildbpath & ".nsf"
 Else
  ' found, return as is
  ChkMailExt = maildbpath
 End If
 Exit Function
 
FErrorHandler:
 ChkMailExt=maildbpath
 Exit Function
 
End Function