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

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. 开发者_Go百科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

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?"