Aim: Set service accounts for SQL Server after installation.
In Server Manager, create a new user with a strong password for the SQL Server instance service. Tick Password Never Expires. For security, the account should be a regular user account, not an admin. If the server is part of a domain, you can create a domain user account (not a domain admin) & manage it via Active Directory.
Launch SQL Server Configuration Manager from the Start menu.
In the SQL Server Services tab, right-click SQL Server (MSSQLSERVER) & open Properties.
In the Log On tab of Properties, chose This Account & enter the Account Name & Password of the newly created user account. If the user’s password is reset, the password in the Log On tab will also need to be updated to ensure that the service starts successfully. Hence ticking Password Never Expires when creating the user to minimise the chances of this happening.
Click OK & when prompted that the action will cause the service to be restarted, click Yes. SQL Server Configuration Manager will automatically apply the minimum required permissions to the service account.
In SQL Server Configuration Manager, the Log On As column will show the new service account.
Repeat the above steps for all services so that each has a different user account associated with it.