In my situation, it's not a network drop or IP block.
I'm using Standalone Converter 5.1
I'm converting Ubuntu 10.04
On the Converter console, the Ubuntu 10.04 would hang at 1% and fail.
Hangs at message: "Connecting to the Converter helper server on the destination virtual machine."
During the conversion process, it hangs at 1%.
I logon to Ubuntu console and issue the commands suggested from TdisalvoOrinoco.
sudo ifdown -a
This shuts down all network interfaces
sudo ifup -a
This starts up all network interfaces
The Converter continued until it completed. The Converter can recover when Ubuntu stop/start the network interface.
The Converter shouldn't hang on Ubuntu at 1%, maybe it's a bug.
Hope this helps someone else.