Error cannot synchronize host cannot contact the specified host в ESXI 5.5

Cause


The issue occurs when the vpxuser password is out of sync with the vCenter Server database and the password on the host or the password has been manually modified.

The vpxuser account is created by vCenter Server when adding an ESX host. It is not recommended to modify the vpxuser account.
http://pyatilistnik.org/error-cannot-synchronize-host-cannot-contact-the-specified-host-v-esxi-5-5/