Posts Tagged 'firewall'

Cannot Connect to Named Instance of SQL Server behind a Firewall

I installed SQL Server 2008 Express on all of my workstations at home this weekend to have a test environment to play with before my 70-453. I had never installed SQL Server across a workgroup before, so it was a learning experience.

Two of the workstations were Windows XP Professional and one was Windows Vista Home Premium. The installs were all fairly uneventful. Being SQL Express intalls, i used the SQLEXPRESS named instance. I opened up TCP port 1433 in Windows Firewall and enabled remote connections.

All set, right? No.

OK. Let’s check everything again.

  1. SQL Server Browser service running? Check
  2. Remote connections enabled? Check
  3. Exception for TCP port 1433? Check

All set, right? No.


After a half hour of searching and five minutes of cursing I discover the SQL Server Browser service uses UDP port 1434. I added the exception and everything is hunky-dory.