Reference number: CH000960

What is the ntdll.dll file?

Question:

What is the ntdll.dll file?

Answer:

What is ntdll.dll?

The ntdll.dll file is a file created by Microsoft that has a description of "NT Layer DLL" and is the file that contains NT kernel functions.

This file is located in the c:\windows\system32 or c:\winnt\system32 directory and can also be found in the c:\i386 directory.

Is this file a security threat?

This file has been flagged as a critical security risk in the Microsoft security bulletin MS03-07 dated March 17, 2003. If you have all the latest updates for your version of Windows you should not be affected by this security risk.

Is this file a spyware, trojan, or virus?

The ntdll.dll file included with Microsoft Windows is not spyware, a trojan, or a virus. However, like any file on your computer it can become corrupted by a virus or trojan. antivirus programs can detect and clean this file if it has become infected. Because this file is part of Windows users should never delete or remove this file if they think it is infected, let the antivirus program handle it.

Can I delete this file?

No, this is a file required by Windows and deleting the file will cause errors with Windows.

I'm getting an error with this file in Internet Explorer

Users who are encountering an error with this file while in Microsoft Internet Explorer can often resolve the issue by removing any third-party add-ons. Additional information about removing Internet Explorer add-ons as well as other basic troubleshooting steps that can be done if this does not resolve your issue can be found on document CHIE.

Additional Information:

• Additional information about why you may be getting a STOP: unknown hard error with the ntdll.dll file can be found on document CH000961.