Connecting to database over loopback adapter with SQL Management Studio under Windows 7

Question

Hi all,

following situation: I am running a MSSQL Server 2005 on a virtual pc. The vpc(Windows Server 2003) and my host system(Windows 7) are connected with a loopback network adapter. I can ping the vpc and I can access the web application running on the vpc. But I am not able to connect to the database from my host system with Sql Managment Studio. Firewalls of both systems are off.

Any ideas?

Thanks

Answer 1

This is connected with security changes made in Windows 7 (and Windows 2008 R2) in comparison to Windows Vista (Windows 2008) and all previous versions of Windows-es, respectively Windows XP (Windows 2003).

This changes prevent connection to loopback ip-address from non-loopback one on Windows 7 (2008 R2) but in any previous Windows-es. This is your case.

Though, it seems undocumented.

See related discussions and follow sublinks in them:

• my question :Security changes between Windows 2008 (Windows 7) and 2008 R2?"
• My answer to "Windows Server 2008 - Connecting to 127.0.0.1"
• My question in msdn WindowsServer "Up-to-date decription of loopback check security feature by MS?"