problem with IIS

Question

hi friends,

   i installed my webproject in IIS . it is opening sucessfully. but when iam trying to connect to mdf database file , it is showing the below error.

please help me in this regard..

thanks in advance..

CREATE DATABASE permission denied in database 'master'.
An attempt to attach an auto-named database for file C:\inetpub\wwwroot\modified student\App_Data\Database.mdf failed. A database with the same name exists, or specified file cannot be opened, or it is located on UNC share