Just tried to update ILO3 on a HP DL 380 G7 from version 1.16 (Dec 17 2010) to one of the latest version 1.55 (Feb 19 2013) but got the following error message in the browser:
The last firmware update attempt was not successful. Ready for the next update.
A quick look in the readme file of the ILO3 1.55 package reveals:
PART NUMBER: 592410-013
FILE NAME: ilo3_155.bin
TITLE: Integrated Lights-Out 3 Firmware 1.55
PREREQUISITE: iLO 3 v1.20
FIRMWARE DEPENDENCY: iLO 3 should be upgraded to v1.20 before upgrading to this version.
But it also works with version 1.28 as intermediate version.