The procedure entry point LogonUserExA could not be located in the dynamic link library ADVAPI32.dll


This is my first blog ever! I am a Support Engineer at Microsoft for three years now. Living my dream – to work with Microsoft!.

You can read more about me – check my profile. To the point now!

On a windows Server 2000 Service Pack 4 when you start an application you get the error message:
The procedure entry point LogonUserExA could not be located in the dynamic link library ADVAPI32.dll” click on OK and the application loads but certain services might fail to start with “Error 1053: The service did not respond to the start or control request in a timely fashion” error message when you start or stop or pause a managed Windows service.

How do we resovle this?
The tool we could use is Process Monitor available at and go through the values to analyse what happens at the point when we get the error message! Sounds boring and cumbersome… Let me share what i found but first the disclaimer 🙂

Important This section, method, or task contains steps that tell you how to modify the registry. However, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For added protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click the following article number to view the article in the Microsoft Knowledge Base:

322756 How to back up and restore the registry in Windows


HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Windows

Then delete the value data for “AppInit_DLLs” which should be “ALockout.dll”

Based on  it states the ALockout.dll is a tool used for trouble shooting and

“Microsoft does not recommend that you use this tool on servers that host network programs or services. You should not enable ALockout.dll on Exchange servers because the ALockout.dll tool may prevent the Exchange store from starting.

Important: Before you install the ALockout.dll tool on any mission-critical computer, make a full backup copy of the operating system and any valuable data”


I hope this has been informative for you and I would like to thank you for reading.

Comments (2)

  1. james says:

    That was an helpful tip , it worked.!


  2. Heather says:

    Worked like a charm . . .

    Thanks so much.

    FYI – Domain Controllers can be added to the list of "Do Not Install This .dll On!" I had to try. Live and learn.

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