Event ID 9001 — IIS Application Host SID Mapping Configuration

Event ID 9001 — IIS Application Host SID Mapping Configuration

Updated: March 24, 2009

Applies To: Windows Server 2008 R2

In Internet Information Services (IIS) 6.0, separate user accounts had to be created for application pools in order to isolate them. In IIS 7.0, mapped application pool SIDs (security identifiers) make this process easier. When a new Web site is created in IIS 7.0, the site receives a new application pool with the same name as the site. The Application Host Helper Service (AppHostSvc) dynamically creates a unique application pool SID based on the application pool name, and the name is mapped to the SID. Web site resources like files and directories can then be granted permissions by using the mapped application pool SID instead of separate user identities. This enables all application pools to run under the same default Network Service account, yet remain isolated.

Event Details

Product: Internet Information Services
ID: 9001
Source: Microsoft-Windows-IIS-APPHOSTSVC
Version: 7.5
Message: The Application Host Helper Service encountered an error while adding the mapping for the application pool name ‘%1’ to its SID. That particular SID is already mapped to another application pool name, causing a conflict. To resolve this issue, please change the name of this application pool. The data field contains the error number.

Change an IIS application pool name

To perform this procedure, you must have membership in Administrators, or you must have been delegated the appropriate authority.

To change the application pool name:

  1. Click Start, click Control Panel, and then click Administrative Tools.
  2. Right-click Internet Information Services (IIS) Manager and select Run as administrator.
  3. In the Connections pane, expand the server node and click Application Pools.
  4. On the Application Pools page, select the application pool you want to rename.
  5. In the Actions pane, under Edit Application Pool, click Rename, type the new name in the rename text box, and then press ENTER or click outside the rename text box.


If Application Host SID Mapping is not configured correctly, Web sites in the affected application pool will fail to serve pages. For this reason, you can verify the Application Host SID Mapping functionality by performing a test browse.

To perform a test browse:

  1. Choose a Web site or an application that is configured to run in the application pool that you want to verify.
  2. Open up your default browser or required client.
  3. Browse to a page in the Web site or application that you chose in step 1.
  4. The client should display the expected output page. If Application Host SID Mapping is configured correctly, the page will be displayed.

Related Management Information

IIS Application Host SID Mapping Configuration

Internet Information Services (IIS) 7.5


Event ID 9001 — TCP/IP Network Connectivity

Event ID 9001 — TCP/IP Network Connectivity

Updated: April 17, 2008

Applies To: Windows Server 2008

Network connectivity allows your computer to communicate with other hosts on your network and the Internet. Connectivity might be full (Internet and intranet), partial (local subnet only), or non-existent.

Event Details

Product: Windows Operating System
ID: 9001
Source: tcpip
Version: 6.0
Message: %2 could not allocate a resource of type %3 due to system resource problems.

Initialize TCP/IP

Refresh the protocol configuration on the network interface by disabling it and then enabling it again.

To perform this procedure, you must have membership in Administrators, or you must have been delegated the appropriate authority.

To disable and then re-enable the network interface:

  1. Click Control Panel, double-click Network and Sharing Center, and then click Manage network connections.
  2. Right-click the network interface you want to disable, and then click Disable.
  3. Right-click the network interface again, and then click Enable.


To perform this procedure, you must have membership in Administrators, or you must have been delegated the appropriate authority.

To verify TCP/IP connectivity:

  1. Click Start, point to All Programs, click Accessories, right-click Command Prompt, and then click Run as administrator.
  2. Click Continue when prompted by User Account Control, and then provide the administrator password, if requested.
  3. Type ping followed by an IP address of another host on the network.
  4. If the ping command succeeds, connectivity is established.

Note:   Windows Firewall might prevent a succesful ping operation. You might need to configure a port exception for the ping to succeed.

Related Management Information

TCP/IP Network Connectivity



The log for database ‘%.*ls’ is not available.

Product: SQL Server
Event ID: 9001
Source: MSSQLServer
Version: 10.0
Component: SQLEngine
Symbolic Name: LOG_NOT_AVAIL
Message: The log for database ‘%.*ls’ is not available. Check the event log for related error messages. Resolve any errors and restart the database.

The database log was taken offline. Usually this signifies a catastrophic failure that requires the database to restart.

User Action

Diagnose other errors and restart the instance of SQL Server if it has not already restarted itself.

Version: 8.0
Component: SQL Engine
Message: The log for database ‘%.*ls’ is not available.
An I/O error related to data integrity has occurred for the specified database. Either the log or data portion of the database could be damaged. SQL Server has made the log for that database unavailable to prevent further data integrity problems. The I/O error that led to the 9001 message should be reported in the SQL Server error log and/or the Windows event logs.

This error could occur because of a failed ROLLBACK operation. In rare circumstances, the ROLLBACK could fail because of the server is completely out of memory, out of buffer pages, or out of log space.

User Action

Run hardware diagnostics and correct any problems. Also examine the Microsoft Windows NT system and application logs and the SQL Server error log to see if the error occurred as the result of hardware failure. Fix any hardware-related problems.

If you have persistent data inconsistency problems, try to swap out different hardware components to isolate the problem. Check that your system does not have write caching enabled on the disk controller. If you suspect this to be the case, contact your hardware vendor.

Finally, you might find it beneficial to switch to a completely new hardware system, including reformatting the disk drives and reinstalling the operating system.


If the problem is not hardware related and a known clean backup is available, restore the database from the backup.


If no clean backup is available, execute DBCC CHECKDB without a repair clause to determine the extent of the corruption. DBCC CHECKDB will recommend a repair clause to use. Then, execute DBCC CHECKDB with the appropriate repair clause to repair the corruption.

CAUTION: If you are unsure what effect DBCC CHECKDB with a repair clause has on your data, contact your primary support provider before executing this statement.

If running DBCC CHECKDB with one of the repair clauses does not correct the problem, contact your primary support provider.