Hmmm... the wild guess, because Converter is newer that your destination:tty with previous Converter 5.1.
Look in the log for following messages:
2015-03-31T01:41:38.041+04:00 [01844 info 'Default'] localVersion is: vim.version.version9 <----- the Converter's version
2015-03-31T01:41:38.055+04:00 [01844 info 'Default'] Remote version is: vim.version.version8 <------- the ESX/VC version
You should disable UAC on source machine, in the case of remote cloning this will be remote machine, in the case of 'this local machine' this will be machine with Converter.
There is a difference between 'Administrators' and user named 'Administrator', there is strong recommendation to use local user name 'Administrator'.
HTH