Are you seeing any errors? When you start/stop a VM, do you see the task in the Recent tasks tab? I understand that you are using the host client. Is the behavior same from the vSphere client as well? With ESXi 5.5, the vSphere client should still work.
Please refer to the first point in 'Known issues' and check if this is relevant as per your setup. Though this version of Host embedded client is currently undergoing development, I would prefer to use old beautiful vSphere c# client till the ESXi version its supported, unless there's specific requirement.
Ah.. that's true
- On hosts using ESXi 6.0 Update 1 or lower and ESXi 5.5 Patch 8 or lower which are assigned a VMware vSphere Hypervisor license (the free license from VMware.com), all modification operations will fail silently. This issue has been resolved in ESXi 6.0 U2 and 5.5 Patch 8.
now everything it's clear.. " all modification operations will fail silently " - that's why I did not see any error
Yes, I have seen this. You won get any error but backend there’s no any changes being made.