Virtual Machine vSphere HA protection issue

For resolving vSphere HA protection issues with message similar to:

The virtual machine failed to become vSphere HA Protected and HA may not attempt to restart it after a failure.

try

Right-click corresponding ESXi host and selete "Reconfigure for HA". This is specially required if summary tab of ESXi host shows non-ok status for vSphere HA.
If the issue is only for a few VMs and not for host then it might be a cosmetic issue while VM is properly HA protected at backend. To solve this you need to disable HA on entire cluster and re-enable it.

Refer:

Anonymous