PRB: Dist. Query Involving External Provider Not Supported When Using Windows NT Authentication

• Microsoft SQL Server version 7.0

SYMPTOMS

Distributed queries are not supported when all of the following conditions are met:

• The distributed query involves an external provider (one that runs out-of-process from the SQL Server).



• The user issuing the distributed query connects to SQL Server using Windows NT authentication.



• SQL Server has been started as a service.



• The SQL Server service runs under the system account and is not allowed to interact with the desktop.

dllhost.exe - DLL Initialization Failed
Initialization of the dynamic link library C:\WINNT\system32\USER32.dll failed.
The process is terminating abnormally.

CAUSE

This problem is a known limitation in COM with impersonating the client's security context when the provider is invoked out-of-process.

WORKAROUND

Change the provider to be invoked in-process using the steps given below.

NOTE: Instantiating the provider outside the SQL Server process protects the SQL Server process from errors in the provider. Only well-tested providers should be run in-process with SQL Server.

1. Under Linked Servers in the Enterprise Manager, highlight the provider and right-click Properties.



2. On the General tab, click the Options button.



3. Select the box beside Allow InProcess.



4. Click the OK button to close the Provider Options window.



5. Click the OK button to close the Linked Server Properties window.

• Use sp_addlinkedsrvlogin to add a login mapping for the user to the remote server. Note that this remote login mapping creates a SQL Server login, so standard security will be used when accessing data from the remote server. Hence, this workaround can only be used by providers that support standard security.

MORE INFORMATION

Note that out-of-process is the default configuration for any external OLE DB provider.

Additional query words:

Keywords : kbSQLServ700
Version : winnt:7.0
Platform : winnt
Issue type : kbprb