The “Database ‘Adventureworks ‘ already exists. Choose a different database name.” error appears if the database with the same name already exists. For example, a user decided to create new database backup with the following command:
CREATE DATABASE Adventureworks
If such database already existed the SQL Server will show the following message:
Msg 1802, Level 16, State 4, Line 4 Database 'Adventureworks ' already exists. Choose a different database name.
Everything that is needed to solve this problem is to choose another database name or delete the existing database.