SQL Install Error: The MOF compiler could not connect with the WMI server

Question

I needed to move (some of) my sql install from C: to D: because of space. SQL installer insists some of it stay on C:. Then I needed (decided) to reinstall it, but sql would not do the reinstall. Gave me error: MOF compiler could not connect with the WMI server. Looked for sqlmgmproviderxpsp2up.mof on windows 10, but not seen. Reset WMI repository, no help. Checked WMI service is running. Cleared sql keys in registry and sql files on disks for cleaner install, but no help. Error message first occurs during install of Slp_Config_Install_Core_WMI_Provider_Cpu64.

[Microsoft SQL Server 2019 Setup. The following error has occurred:

The MOF compiler could not connect with the WMI server. This is either because of a semantic error such as an incompatibility with the existing WMI repository or an actual error such as the failure of the WMI server to start.]

All help provided is appreciated. Thank you.

Answer 1

There were several fragments from previous install attempts lodged in the windows registry. Once those fragments were removed from the registry (which took some time and effort), the program installed smoothly.

Incidentally, Windows 10 did not report the correct folder (space) size in this instance. But a utility called TreeSize did report the correct folder size. Moving (some) of SQL from C: to D: did help.

Answer 2

• The MOF compiler could not connect with the WMI server.

Its happen your previous sql server uninstallation improper. That's why you have to uninstalled previous version from your system and then install new version.

https://support.microsoft.com/en-us/topic/fix-problems-that-block-programs-from-being-installed-or-removed-cca7d1b6-65a9-3d98-426b-e9f927e1eb4d

after download troubleshoot and perform uninstalled all sql server and using uninstallation of your old version.

Answer 3

Laru: About one week earlier my C: drive had nearly 110GB free (24% free). Then more recently Windows Explorer said my C: drive had only 6% free (with no additional big files added by me). So I started looking for a space consumption (memory leak) problem on drive C:.

This link was the first I came across. https://answers.microsoft.com/en-us/windows/forum/all/my-c-drive-is-full/b40fd83a-d55e-47e9-96db-74bd1d4a89e6

The comment on that thread by DaveM121 says Windows Explorer is useless (in this situation). I am inclined to agree with that. I had a space leak on my machine and Windows Explorer just was not finding it for me. Then I started using TreeSize which did find it for me (right away).

This link was the second I came across. https://www.groovypost.com/howto/map-hardrive-usage-find-hidden-files-windows-10-treesize-freeware/

On my machine, TreeSize said my C:\Program Files\Microsoft SQL Server folder was very much larger than the size value reported then by Windows Explorer. So I uninstalled SQL Server and reinstalled it again, but put some on drive D: (to save some space on C:, which is history by now).

I did not accurately know just how big the (non-leaking) SQL folder was when I decided to re-install it to D: drive. But I do now. Laru, your comment that the (non-leaking) SQL folder could (or should) have stayed on drive C: is correct. Even so my SQL install is working correctly, although it is split over the two disks. At this point I have learned how to install and un-install SQL so very well, that I can change the install configuration later efficiently if the need arises.

The total amount of space freed up on C: by the reinstall should only have been 14.8GB (see count below). So Laru you probably came to think there was something wrong. And indeed there was (a memory leak). But there was also about another 60GB freed up moreover on C: by the reinstall, which is what I was trying to recover. So again I think there must have been an on disk C: memory leak. The SQL reinstall appears to have fixed that completely now. Thanks to TreeSize for finding the right problem folder (right away).

C:\Program Files\Microsoft SQL Server, (4.8GB) C:\Program Files (x86)\Microsoft SQL Server, (0.163GB) C:\Program Files (x86)\Microsoft SQL Server Management Studio 18, (1.1GB)

D:\Program Files\Developer_ENU, (1.5GB) D:\Program Files\Microsoft SQL Server, (11.0GB) D:\Program Files\Microsoft SQL Server Reporting Services, (0.309GB) D:\Win_10_Pro_Stores\Installed Softwares\MS SQL Server, (2.0GB) The D: sum amount is 14.8GB (saved from C:)

Hope this clears the confusion.

Regards.