Hello All, I am getting the same error.
VirtualInfrastructure.Utils.ClientsXML threw an exception
I am running, or attempting to run VMWare vSphere Client 6.0.0 on Windows10 to ESXi 6.0.0 host.
When starting vSphere Client it takes several minutes to actually start but eventually I get the GUI and attempt login to my target IP adddress, userid=root and passwd.
It just sits there for a long time (again, several minutes) before throwing error listed above.
I have created the TMP and TEMP directories as someone mentioned, did not work for me.
I have disabled UAC, and the Windows Firewall, rebooted - still nothing.
I have tried vSphere 5.5.x and it performs the same way.
Now, I can use PuTTY (SSH) and FireFox browser to get to the ESXi host without any problems or delays.
Any help/suggestions are appreciated.