Hi:
Someone has given me a UDF which is coded as follows::

Private Function WorkbookIsOpen(wbname) As Boolean
'   Returns TRUE if the workbook is open
   Dim x As Workbook
   On Error Resume Next
   Set x = Workbooks(wbname)
   If Err = 0 Then WorkbookIsOpen = True _
       Else WorkbookIsOpen = False
End Function

I want to implement this so that it can be called for a sp[eciofic workbook. I have
presently tucked it in the same area as the macros, but when I call it I get a errpr "Sub
of Funcvtion undefined". The call is corrfect, but somehow the function isn't being
excited.

Can some one give me a step by step outline of how I record a functions such as this?

Thanks

John Baker