The Symantec Endpoint Protection Manager (SEPM) is not updating its definitions automatically, but when luall.exe is manually run by the administrator LiveUpdate is able to successfully download and process new contents.
Liveupdate failed. Return code=2.
Windows authentication is not configured with the proxy
Remove the windows authentication check from the proxy settings of the SEPM console.
Definitions will then be able to update per the schedule configured without any manual action from the administrator.
Windows server 2008 R2 64-bit
Proxy server between the SEPM and the Internet LiveUpdate source servers