Same Problem here. I have two VMs stucking at 72%. My ESXi hosts are on Version 6.0
Last days I had one VM for days in that Status, suddenly the Task disappeard and I couldn't migrate the VM anymore. The VM was a virtual Desktop so I decided to recompose it again. I was able to delete it from the view Manager, but on the storage the machine was still there. manually deleting Fails with error: connot delete file