Database mirroring must be removed before you drop SQL Server database – Error 3743

If you try to drop a mirrored database in SQL Server before you remove mirroring you will get the following error:

Msg 3743, Level 16, State 1, Line 1
The database ‘Database_Name’ is enabled for database mirroring. Database mirroring must be removed before you drop the database.

You need to disable mirroring before deleting the database.
To disable mirroring run the following code:

ALTER DATABASE [Database_Name] SET PARTNER OFF;
GO

Now the database mirroring is removed and you will be able to drop the database.