Exception Details: System.Security.SecurityException: Request for the permission of type 'System.Data.SqlClient.SqlClientPermission, System.Data, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' failed.

Do you have any custom webparts in the restored site? It looks like a CAS (Code Access Security) Policy issue, where the webpart connects to a SQL database and the current level of trust doesn't allow that type of permission for sql connections. If this is the case you can create a CAS policy (recommended) or raise the level of trust in the web.config.My SharePoint Blog - http://www.davehunter.co.uk/blog

yes, i have created custom webpart, please tell me how to raise the level of trust in the web.config