title: Cannot Login To Default SQL Server Instance
body: <p>I brought my laptop home from work hoping I could get some tasks done over the weekend. Unfortunately, I couldn't login to SQL Server using <code>Windows Authentication</code>. I've checked the <strong>SQL Server Configuration Manager</strong> and the instance (<code>MSSQLSERVER</code>) is set to <strong>Log On As</strong> <code>Local System</code>, which supposedly means that I should be able to login fine using Windows Authentication... or am I missing something here? Note that in the login window, I tried a lot of different combinations and it always keeps telling me that connection failed because the server is not accessible or I'm not authorized to access it.</p>
  
  <p>A little background about how the instance was installed: I installed and configured it myself. I chose the <code>Mixed Authentication</code> mode and gave a password to the default <code>sa</code> user (which isn't working either by the way). The thing I suspect could be the problem is the fact that I installed the SQL SERVER instance when I was logged in as my <code>Domain User</code> at work (<code>DOMAIN\UserName</code>). Now I'm at home and I do not have access to the LAN at the office, so I'm logged in as the <code>{COMPUTERNAME}\Kassem</code> user.</p>
  
  <p>Any thoughts?</p>