I have this query and I get the error in this function:
var accounts = from account in context.Accounts
from guranteer in account.Gurantors
I am using web service in my tool, where those service fetch the stored procedure. while more number of client tool fetches the web service, this problem arises. I have fixed by specifying the Synchronized attribute for those function fetches the stored procedure. now it is working fine, the error never showed up in my tool.
[MethodImpl(MethodImplOptions.Synchronized)]
public static List MyDBFunction(string parameter1)
{
}
This attribute allows to process one request at a time. so this solves the Issue.