Perfect solution: MSSQL & quot; a previous program has been installed on the installation computer to create a pending file operation & quot;

Steps:
1) Add/delete programs to completely delete SQL server.
2) Delete the SQL server Directory that has not been deleted.
3) Open the Registry Editor, find the PendingFileRenameOperations project in HKEY_LOCAL_MACHINE \ SYSTEM \ CurrentControlSet \ Control \ Session Manager, and delete it. In this way, you can clear the temporary installation project.
4) Delete the SQL server-related keys in the registry.
Step 1 is the most important !!! Here, we found not the folder on the left, but from the right !!! The tree folder on the Left does not have this project, and there is only one FileRenameOperations. It is useless to delete it.
Also, the SQL server-related keys in the registry include:
HKEY_CURRENT_USER \ Software \ Microsoft SQL Server
HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft SQL Server
HKEY_LOCAL_MACHINE \ SOFTWARE \ Microsoft \ MSSQLServer
All microsoft SQL SERVER and MSSQLSERVER are deleted!
After successful installation. the logon fails. the table cannot be returned ("Unexpected error occurred during this operation" is displayed when you want to create a new table. keep trying and finally succeed! The process is really annoying ~~~~~~~ The procedure is as follows:
In the control panel-management tools-service, find one of MSSQLSERVER. Change the service account information of the MSSQLSERVER service to a user dedicated to the SQL service.
My practice is to select the logon identity "Local SYSTEM account ".
Set the logon option in MSSQL Enterprise Manager to "WINDOWS Verification" only"
OK.
I hope you will not encounter so much trouble during installation or reinstallation.