# Authentication options

Remote computer authentication verifies that you are connecting to the correct Windows-based computer. There are three available authentication options.

- Always connect, even if authentication fails

  Even if Remote Desktop Connection cannot verify the identity of the Windows-based computer, it connects anyway. This is the least secure authentication option.

  Note If a Windows-based computer is running Windows XP or earlier, or Windows Server 2003 Service Pack 1 (SP1) or earlier, it cannot provide its identity for verification. If you know that the Windows-based computer is running one of those earlier operating systems, you can avoid authentication warnings by choosing Always connect, even if authentication fails.

- Warn me if authentication fails (default setting)

  If Remote Desktop Connection cannot verify the identity of the Windows-based computer, it warns you so that you can choose whether to continue with the connection. This authentication option enhances security compared to the Always connect, even if authentication fails option.

- Do not connect if authentication fails

  If Remote Desktop Connection cannot verify the identity of the Windows-based computer, you won't be able to connect. This authentication option uses enhanced security features when you connect to a computer that is running Windows Vista. This authentication option enhances security compared to the other two authentication options.

  Note If you select this option, you won't be able to connect to computers that are running versions of the Windows operating system that are earlier than Windows Vista.

### See also

I can't connect to the Windows-based computer