We have recently had an annoying issue with machines taking a very long time to get to the ALT-CTRL-DEL screen on boot up and also taking ages to shut down and do anything in Windows.
We found a few hot fixes for this issue, but when we tried to run them, we found that they would just hang as well and not run.
After going through endless log files that gave us no information at all, we finally got to the end of it - it is partly to do with a corrupt WMI repository.
To fix this problem is a long process and you will need to run a batch file which will completely rebuild your WMI repository to clear the issue. This batch file is available to download further down in this guide so keep reading!
Please note that doing this will rebuild your WMI so you do so at your own risk!
First of all, you need to login to the affected machine with a local admin account that has previously logged into the machine, this should allow the machine to login a little quicker than it trying to create a new profile (of which it may never complete anyway).
Once you are logged in, click Start, then in the search box type: services.msc and hit enter.
You then need to locate the Windows Management Instrumentation service and double click it. Do not stop the service as it may crash your Windows, just change the drop down menu to Disabled, click Apply and OK.
You then need to copy the fix files locally to your local drive (for this guide I'll be using C:\WMIFIX). The fix files are the batch file that will rebuild your repository and the other is the Windows Hot Fix that you need to run (note that x86 and x64 hot fixes are included in the below download).
Once you have copied these files to C:\WMIFIX reboot your machine and pressing F8 boot into Safe Mode (important, make sure you choose just Safe Mode and not Safe Mode with Networking or anything else...)
You will then get to the ALT-CTRL-DEL Screen, again, login as a local admin account. Once in, double click the batch file that you copied into your C:\WMIFIX folder, this should then disable all necessary services and completely rebuild your WMI - this sometimes can take some time, so don't think it has crashed, let it finish.
Once this has finished, you can then reboot your machine again and login again as a local admin. You should notice that the machine is now working slightly quicker.
You should then run the Windows Hot Fix that you copied to your C:\WMIFIX earlier (depending on x86 or x64). Let it install, then reboot and login as your standard user - you should find that your machine is now back to normal again.
Note that running the batch file fixes the problem, running the hot fix keeps it from happening again!
I've had a lot of people contacting me asking why this happens and why this fix works - the simple answer to every one of these questions is - I don't know! I know why it worked for me, but your problem could be different.
If you want to know what my problem was - I had a failed upgrade installation of my SCCM environment meaning that my client machines could not report their ever growing hardware inventories. This meant that the WMI repositories on the client machines got bigger and bigger until the machine wouldn't work correctly any more. Running the batch file cleared the registry and the hot fix seem to keep it at bay.
The real fix in the end for me though was that I had to rebuild my SCCM environment and I've had no issues since. So my advice would be to find the source of the problem and fix it!
I'd like to hear if this helps you, so if you try it, please remember to leave a comment with your feedback...