MSSQL Server Management Studio: Value cannot be null

You are installing MSSQL Server 2008 R2 and when you login to the MSSQL Server Management Studio, below error pop up.

MSSQL Server Management Studio - Value cannot be null

Solution

In our case, we faced the error while installing the MSSQL Server 2008 R2 with SAP system. The error occurred when you have installed the MSSQL Server 2008 R2 using username A (example) and launch the MSSQL Server 2008 R2 using different username.

If you are done installing the MSSQL Server 2008 R2, you can ignore the error. You can proceed the SAP installation as the installer will grant the appropriate authorization to other users to be able to launch the MSSQL Server Management Studio.