Windows: Troubleshooting WMI errors and repairing WMI

WMI Requirements

Windows Management Instrumentation (WMI) service is a requirement for the Nanitor agent on Windows.

WMI is a core part of Windows that allows programs to query information about the computer. Nanitor uses this to fetch various information such as operating systems, users, and more.

In some cases, the WMI service can stop working or the WMI repository can become corrupted and stop working properly. Possible reasons may be: - System upgrades - Running out of hard disk space - Memory or other hardware problems

The following instructions describe how to diagnose and repair WMI problems. Note that those problems cannot always be resolved, and one may need to reinstall Windows to remediate them. Furthermore, if WMI has been corrupted, there is a chance that other system files may have been corrupted. A reinstall may be the best option if more problems surface.

WMI Diagnostics

First, we can check if the WMI Winmgmt service is running by running the following command as Administrator in PowerShell

Get-Service | findstr Winmgmt

the output should look like

PS C:\Users\Administrator> Get-Service | findstr Winmgmt
Running  Winmgmt            Windows Management Instrumentation

If the WMI service is running, the text should be "Running". If it is not running, then to start it can run:

Start-Service Winmgmt

To see if WMI is available and working, we can run a basic WMI query in PowerShell (as Administrator):

Get-WmiObject -query "SELECT * FROM Win32_OperatingSystem"

The output should look like this:

PS C:\Users\Administrator> Get-WmiObject -query "SELECT * FROM Win32_OperatingSystem"
SystemDirectory : C:\Windows\system32
Organization    :
BuildNumber     : 14393
RegisteredUser  : Windows User
SerialNumber    : 00377-90014-64864-AA792
Version         : 10.0.14393

If this is not working, there is something wrong with the WMI.

Try rebooting the computer. That often fixes WMI problems, then recheck with steps 1-2. If that is not solved, then can proceed with the next step. 4. To check and validate the WMI repository, run:

winmgmt /verifyrepository

the output should look like

PS C:\Users\Administrator> winmgmt /verifyrepository
WMI repository is consistent

If the WMI repository is consistent, that should be OK. Otherwise, we may need to try to repair the WMI repository.

Repairing the WMI repository

Before attempting a repair, we need to first:

Note that the repair might fail and the state on the machine could become worse. Some programs may not work as they used to before.
You might end up needing to reinstall Windows on the device
Back up any important data and programs on the computer.
To attempt a consistency check, followed by a repair. Run in PowerShell (as Administrator).

winmgmt /salvagerepository

This performs a consistency check on the WMI repository, and if an inconsistency is detected, rebuilds the repository.

Next check the consistency again:

winmgmt /verifyrepository

If the repository is now consistent, that is great. Otherwise, one may need to reset the repository.

Reboot the computer and check the WMI state as in the Diagnostics steps 1-4 above.

Proceed with caution and remember to back up any important data. 4. To reset the repository, run as Administrator:

winmgmt /resetrepository

You should see the message WMI Repository has been reset. If you see an error message instead, make a note of it.

5. Reboot the computer and re-run the verification steps (Diagnostics steps 1-4). Hopefully at this point everything is OK.

Otherwise, you may need to reinstall Windows on the computer or trying to do a system repair.