Problem with connecting with the database

I have installed sql server 2012 in my machine. I  have SA account which works fine with sql server management studio.

But when i try to login from the same user SA in my application server explorer. I am getting error Login failed with the User SA

In Server Explorer Trying to connect from uses SA

I get the Login Failed with User SA Error Please See Image

http://i63.tinypic.com/21dmqkj.png

When I login from SQL Server Management Studio It works fine.

Where is the problem

Thanks 

Farooq

Additionally I am using the connection string as below

<connectionStrings>
<add name="StudentManagementEntities" connectionString="metadata=res://*/Model1.csdl|res://*/Model1.ssdl|res://*/Model1.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=.;initial catalog=StudentManagement;user id=sa;password=abc12345;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />

</connectionStrings>

The password i used is the same for sa user which i used in sql server managment studio and it works fine there;