I have a VBA/ADO macro that fetches some simple results from a SQL-Server 2008 stored procedure.

Every once in a while I get a DBNETlib preloginhandshake error. I can choose to end the macro, close Excel, reopen and rerun it without any problems.

Normally I would imagine it to be some config error on the server, but as its pretty random I can't seem to find the logic in it.

Different client pc's, same error.

The server is configured to listen on remote tcp/ip requests - otherwise it wouldn't run at all I gather, and we have other client programs accessing the server with no problem, so I figure it might relate to some ADO/OLEDB issue.

I've enclosed the provider string.

Code:
GIDdns = "provider=SQLOLEDB;Data source=Gramex-NAV;initial catalog=Gramex_Excel;User ID=XXX;Password=XXX"
Any ideas?

Cheers, Trin