To do this please follow the steps bellow .
Login to the plesk
Click on database icon -> Select data base--> Tic user name and click on Webadmin icon at Top
Then click on database name in ASP.net Ent.Manager.
Clcik on users--> tick all except bottom two --> Click on save--> Click on permisssions--> Set necessery permisions .
Your data base is now ready for operation