SEP 12.1.5 disabling internet based on "traffic has been blocked from this host svchost.exe"

We use Symantec Endpoint Protection in an unmanaged scenario in our small network.  In certain cases, some staff get their internet access disabled when SEP says "traffic has been blocked from this: svchost.exe"

The quick fix:

In SEP

1. clicking on Options next to Network Threat Protection

2. Click "Configure Firewall rules"

3. Find "Block UPnP Discovery" and change it from BLOCK to ALLOW

Symantec Endpoint Protection LiveUpdate fails

I had an unmanaged SEP install that failed to update itself - even after I uninstalled and resintalled.

Turned out the answer was to update from LiveUpdate 3.3 to LiveUpdate 3.5 via this link:

ftp://ftp.symantec.com/public/english_us_canada/liveupdate/3.5/lusetup.exe