I use update manager and added the .zip. The upgrade starts with maintanence mode and after a few minutes the host reboots, but it reboots into the old 3.5 version and i get an error saying "cannot upgrade firmware on specified ESXi host"...
????
I have now started all the VMs again and wonder what to do next? What could cause an upgrade to fail like this? I have done it at many other clients the exact same way and it always worked just fine??
/Henrik