Recently I spent some time upgrading our corporate VMware environment from ESX4.1 to ESXi 5. Fun times I know. For most of the hosts, I was able to use the update manager to upgrade and only one host was short on space that required a full re-install from CD.
The upgrades weren’t without incident. I had the unfortunate incident of running into an error of “The Unlicensed license for host <hostname> does not include vSphere HA. Upgrade the License”.
Luckily, the fix is really easy. Simply remove the host from your vCenter and re-add. Sure you’ll need to re-add it to your dVS if you have one and re-attach your host profile if you are using those. But in the end, its thankfully a very painless fix to what I would call a bug.