Thanks for the update. All is now logical with respect to this problem.

>Actually, it turns out that there's nothing magic about the c:\winnt\system32 folder. I found that VFP will connect in any folder other then the application folder.
>
>The real problem all along, was all due to a stray TNSNAMES.ORA file that had been copied at some point into the application folder. If the file exists in the default folder, then it gets used instead of the one that is in c:\orant\net80\admin. Back when the file got copied into the application folder, it didn't break anything since it was the same as the one in the c:\orant\net80\admin folder. Then once we changed the firewall, the TNSNAMES.ORA file was no longer allowing connectivity.
>
>Thanks to all who looked into this issue
>
>David
>
>>Does it also work if you add C:\WinNT\System32 to the SET PATH command in your app?
>>