Fix for Login failed for user “. The user is not associated with a trusted SQL Server Connection:

To set the DisableLoopbackCheck registry key yourself, follow these steps:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key:
   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. Right-click Lsa, point to New, and then click DWORD Value.
4. Type DisableLoopbackCheck, and then press ENTER.
5. Right-click DisableLoopbackCheck, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Quit Registry Editor, and then restart your computer.

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Wehould now find that the connection will complete successfully. Another place to check is in event viewer. For this particular error we had 3 events logged in event viewer:

1. Failure Audit :: Login Failed for user ‘\’. (CLIENT 127.0.0.1)

2. Error :: SSPI handshake failed with error code 0×8009030C while establishing a connection with integrated security; the connection has been closed. (CLIENT 127.0.0.1)

3. Failure Audit :: Login Failed for user “. (CLIENT 127.0.0.1)

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