I’ve been trying to convert a physical machine for a couple of days now. Each time, I’d only get ~2 to ~3MB/s. It was terrible. I finally found the solution here. After the change, I got 10x the speed, ~28MB/s. Here’s the solution:
Choose Start > Run … and enter this path…
%ALLUSERSPROFILE%\Application Data\VMware\VMware vCenter Converter Standalone
Change UseSSL to false.
Important! Restart the Worker service.
That’s it. If it doesn’t work, check the article linked to above for more ideas.