Dan,

I don't think you can use the udl file with SQL Pass-Through, the formats of the connection string are different. You can use the udl directly in ADO:

oConn.ConnectionString="File Name=< fullpath >/myfile.udl"

You can use a DSNLess connection with SPT:

SQLSTRINGCONNECT("Driver={SQLServer};Server=MyServer;Database=Pubs;UID=;PWD=")

Also, if you copy the udl with the FILETOSTR function you will have to do some parsing since there is more than just the connection string in the file. Take a look at a udl with notepad. HTH