Thank you so much jlg89, this was my exact predicament, the installer looked and claimed it completed but I was left with an OS and no Asterisk.
Finally burning it to a disc and installing went through a very different process, I now have a complete Asterisk / FreePBX install 
I went thought this same headache. A couple days wasted chasing this one down.
Many thanks for jlg89 for doing the regression testing that should have been covered by FreePBX.
I am really disappointed that there is not better support for non-DVD based systems. I have a downed customer that needs a rebuilt system and I don’t have access to an optical drive. Your product claims to have a USB ready image but that’s clearly not “stable” or even usable at this point. Worse, it pretends to work but fails without any warnings or errors to the user, leading them down a wild goose chase on why.
Thanks for the work you did chasing this down - you saved my brick wall from unneeded abuse from my frontal cortex.
I was having the same problem installing version 14 on my machine. It’s a clean installation off a USB stick. I made two attempts to install the software. Both times failed with the same error. Finally I configured the Ethernet for a static IP and a host name. What ever the difference the installation is successful. I suspect the previous attempts were missing the network connectivity during the installation.