SQL Server Installation Error - Could Not Find Database Engine Startup Handle

Problem 1:

I have SQL Server 2008, R2, 2012, 2014, and 2016 installed on a single machine on Windows 8.1 Professional. Everything, especially the SSRS part, had worked great. Lately, I upgraded the OS to Windows 10. Today, however, I notice that the SSRS part does not work anymore. The Reporting Service Configuration Manager complains invalid namespace.

Solution  1:

I repaired it for the default instance (SQL Server 2014). But I could not repair the other named instances.

Problem 2:

I decide to uninstall all of the instances. During the reinstall, some of the previous instances still show up. So I decide to clean up the registry, the installation directories and files, and the user accounts. But I got the following errors:


The virtual account used in installation does not have sufficient privilege.

Work Around:

Choose the system account instead of the default virtual accounts during installation for SQL Server Database Engine Service and SQL Server Agent Service. After the successful installation, we can change to lower privileged accounts for the service accounts.