I received same message when trying migrate VM from ESX2.5 to esx3.x.
I boot old VM from Coldclone.iso cd and everything goes fine until I get to Destination Type where I get above error.
No option except OK is available, which gives me another prompt for ESX or Virtual Server Login with User name and Password.
I tried VC server or complete ESX server name to no avail.
I am using VMWare Converter 3.0.0 build-39557.
Cab anyone help?
Did you try using the IP address? That may be necessary if DNS is not properly set up to look up the host names for VirtualCenter or ESX Server.