Your syslog source is sending an invalid syslog packet (per the RFC). In this case, the packet is too small to be valid. You can enable a setting in Orion to have the syslog service "fix" these invalid packets. Executing this SQL on your database should fix this issue and will enforce the RFC on all packets through the system.
SET CurrentValue = 1
WHERE SettingID LIKE '%SysLog-EnableRfcRelay%'
Then restart your Syslog Service.
Please let me know if I can help any more with this issue.
This not helped me. Also my solarwinds not showing updated events some times, this happens regularly with in one or two days gap.
I know its old thread but I am getting the same error as " Error Decoding Packet Invalid Packet Size Original packet is: "