Hi Michael,

How can I use a full path name as a range argument
in a user defined function

You could try putting the link in another cell and reference that cell
in the call to the udf. Another option is to define a name that refers
to the other workbook and use that name in the call to the udf.
e.g. :

Insert, name, define

Name: ExternalLink
Refersto:='c:\data\[test.xls]Sheet1'!$A$1:$c$4

Then in another cell:

=YourUDF(ExternalLink,Otherargs)

Regards,

Jan Karel Pieterse
Excel MVP
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