I am running the Windows version 13.0.0(76681). I just tried installing SP3, and get the same error response. The InstallerLog.txt file shows the following at the bottom:
The updater cannot hook up to the update server. Please check your Internet connection, disable your firewall and anti-virus software, and try again.
Exception Type: socket.error
Exception Value: (10061, 'Connection refused')
Exception Stack:
File "InstallerScript.pyc", line 1234, in GetAndInstallUpdates
File "httplib.pyc", line 800, in request
File "httplib.pyc", line 823, in _send_request
File "httplib.pyc", line 794, in endheaders
File "httplib.pyc", line 675, in _send_output
File "httplib.pyc", line 642, in send
File "httplib.pyc", line 626, in connect