The Error "Login failed for user"

When I deploy the website to my server, it comes out the error: Login failed for user"xxx/xxx", more detail as below:

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.
Exception Details: System.Data.SqlClient.SqlException: Login failed for user 'NT AUTHORITY/LOCAL SERVICE'.

After searching from the internet, I know that reason of it. The problem is the permisstion of the IIS as the default permisstion is low. Then we need to configure the settting of the Application Pool. Operation Steps:

Step 1: Open the Internet Information Services (IIS) Manager

Step 2: Click the Application Pools and select the web site you want to configure.

Step 3: Change the Identity to Local System in the Advanced Setting and click ok.

After that, your web site works. Hope that can help you.

Reference:http://www.cnblogs.com/longgel/archive/2010/05/13/1735010.html