Error: "Download failed with error 28. URL: http://definitions.symantec.com/defs/rapidrelease/ennlu.lin." in JLU-Controller log.
The error code 28 in the JLU Controller logs indicate a network timeout.
SMG is unable to download the complete antivirus definition package before exceeding the download timeout. The network connection may be too slow or too congested to fully download the anti-virus definitions.
If you are configured for Rapid Response Updates, change the LiveUpdate configuration to Automatic updates on the following schedule and increase the timeout value.
Click on the Malware tab.
Click on LiveUpdate.
Select "Enable automatic updates on the following schedule"
Configure the schedule to check every day and every hour.
Increase the Rapid Response and automatic update timeout.
Test and modify as necessary.
If this is a recurring issue, the only remaining solution would be to position a LiveUpdate Administrator (LUA) server on a location in the company network that has fast access to the Internet. This LUA server can download the definitions that SMG needs and distribute them to an internal location that the SMG can access quickly. The SMG can then be configured to retrieve content from this internal Distribution Center (DC), rather than from the Internet LiveUpdate source servers via (Malware > Liveupdate > Download virus definitions from a LAN host).