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Cause of Error in SQL Server ” Cannot use the special principal ‘sa’. Microsoft SQL Server, Error: 15405 “

when importing a database in your SQL instance you would find yourself with Cannot use the special principal ‘sa’. Microsoft SQL Server, Error: 15405 popping out when setting the sa user as the DBO of the database.

To Fix this Error in SQL Server ” Cannot use the special principal ‘sa’. Microsoft SQL Server, Error: 15405 “

Open SQL Management Studio and Click New Query. Type:

USE mydatabase
exec sp_changedbowner ‘sa’, ‘true’

To change the owner of the database, you can use sp_changedbowner or ALTER AUTHORIZATION command

Another Cause of Error in SQL Server ” Cannot

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