We just replaced an older Windows 2000 sp4 server with a new Window 2003 Standard Edition sp2 server to run our batch processing. We noticed that when the SQL command times out we now get the following error in the ADO command object error collection.
[DBNETLIB][ConnectionWrite (send()).] General network error. Check you network documentation.
Native Error: 11
SQL State: HY018
msado15.dll version 2.82.3959 is on this server.
On other servers running Windows 2003 Enterprise Edition sp1 the error on the ADO command object is normal with.
Native Error: 0
SQL State: HYT00
msado15.dll version 2.82.1830 is on this server.
The SQL server they are talking to is on the other side of a firewall. It is SQL 2005 sp2 running on Windows 2000 sp4.
I have also tested this on a Windows 2003 sp2 server that doesn't have to cross a firewall and get the correct Timeout error. It also has the same version of msado15.dll as problem server.
The application is a collection of VB6 Components that are running in COM+ applications. I have isolated the test application to our one SQL interface component and have build a test vbs that can reproduce this on demand. The VB6 Components were not modified in any way for this change and have been working fine for many years prior to this.
All other aspects of our batch processing works as expected. Transactions are working fine. As long as the SQL doesn't timeout everything is normal. DTCPing was used to ensure both servers have correct ports open to allow DTC traffic. Checked the SynAttackProtect setting on SQL and this is not an issue since other clients have no problems.
One point I would like to add is that this new server was initially setup with a temporary server name and then was changed to use the name of the original server on move day. Don't know if this has any impact or not.