Windows Update on Windows 7 hangs on Checking for Updates

Hi all,


Running Windows 7 Home Premium edition, x64 edition. Windows Update used to work but stopped working several months ago. Now it hangs forever on "Checking for Updates..."  During the time it hangs, TrustedInstaller.exe runs to 50% CPU usage and stays there. This process can be killed but it relaunches in a few seconds. I have tried letting it run overnight, to no resolution.


I have run Fix It multiple times, before/during/after running Windows Update. If Windows Update is currently Checking for Updates, then running Fix It will cause Windows Update to exit without finding any updates (can't be right -- as I said, it's been months), and the next time Windows Update runs, it hangs again on Checking for Updates.


I have found related threads in the forums but no clear answer. I have tried the manual instructions at In particular, the instructions to register the BITS and Windows Update .dll files (Step 6) do not all work, as follows:


  • mshtml.dll, shdocvw.dll, browseui.dll, and qmgr.dll fail with the error: The module [name of the .dll] was loaded but the entry-point DllRegisterServer was not found. Make sure that [name of the .dll] is a valid DLL or OCX file and then try again.
  • msxml.dll, gpkcsp.dll, sccbase.dll, slbcsp.dll, wuaueng1.dll, wucltui.dll, wuweb.dll, and muweb.dll do not exist in my System32 folder.


Finally, I am unable to download a new Windows Update agent (Step 11). The download at does not seem to apply to Windows 7.


I last successfully installed updates on 7/2/2011, including the following Updates for Windows 7 for x64-based systems: KB2552343, KB2533552, KB2547666, KB2545698, KB2534366, KB2541014.


Thanks for any informed help.




Rohit, thank you for the suggestion. Your Method 1 was a point in the right direction.


For anyone else experiencing this problem, the conflict was with "Windows Module Installer," which is the parent process that calls TrustedInstaller.exe. I'm not a Microsoft tech, but for my situation I recommend the following:


1)  Run msconfig.exe as administrator.

2)  Under Services, deselect Windows Module Installer. Apply and reboot.

3)  Windows Update now runs. Download and install any updates.

However, other software updates and installations may not run anymore.  Therefore:

4) Leave Windows Update set NOT to check for updates automatically.

5) Run msconfig.exe again and reselect Windows Module Installer. Apply and reboot.

6) Set yourself a reminder to run Windows Update periodically by following these same steps.


Note that this is a workaround, not a solution. The real problem is that Windows Update is not playing well with Windows Module Installer.




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Question Info

Last updated July 3, 2021 Views 33,620 Applies to: