SQL19 express installation Error

Question

I'm trying to install 'Microsoft SQL Server 2019 Express' with below steps:

Used Custom Installation step

From SQL Server Installation Center: I've selected 'New SQL Server Standalone installation'

In the feature selection, I've selected

a. Database Enginee Services

b. SQL SERVER Replication

c. Clients tool connectivity

D. Clients tools backward compatibility

E. Client tools SDK.

In Database Engine configuration, I've selected 'Mixed Mode' and entered correct password for 'sa' user

Following all the above steps, in the installation progess steps. I'm getting below error:

"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."

Any help provided is appreciated. Thank you!

Note:

I have SQL 2008 and 2017 instances installed on my system. I have also tried to remove those instances and try new installation but still I'm getting the same error.

Answer 1

Hi @Pramod Kumar,

Seems like incomplete uninstallation of SQL server and you are not able to install in SQL server in the machine.

Please refer to this thread:

https://stackoverflow.com/questions/63636622/sql-install-error-the-mof-compiler-could-not-connect-with-the-wmi-server

You can download this troubleshooter. It help you automatically repair issues when you're blocked from installing or removing programs. It also fixes corrupted registry keys.

There is another way.

Please follow the below steps to remove all components of previous installed SQL Server completely:

1. Remove all SQL Server components from 'Programs and Features'
2. Backup the registry
3. Delete the following keys in regedit:

--HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server

--HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer

1. Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall and delete all the sub-keys referencing SQL Server
2. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services and delete all the keys referencing SQL Server
3. Reboot the machine

In addition, please use an administrator account to reinstall SQL Server on your computer(Right click->run as administrator).Please refer to this thread:

https://stackoverflow.com/questions/63636622/sql-install-error-the-mof-compiler-could-not-connect-with-the-wmi-server

You can download this troubleshooter. It help you automatically repair issues when you're blocked from installing or removing programs. It also fixes corrupted registry keys.

There is another way.

Please follow the below steps to remove all components of previous installed SQL Server completely:

1. Remove all SQL Server components from 'Programs and Features'
2. Backup the registry
3. Delete the following keys in regedit:

--HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Microsoft SQL Server

--HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer

1. Go to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall and delete all the sub-keys referencing SQL Server
2. Go to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services and delete all the keys referencing SQL Server
3. Reboot the machine

In addition, please use an administrator account to reinstall SQL Server on your computer(Right click->run as administrator).

Regards，

Zoe Hui

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