libcurl error during apt-get udpate

Hi.

So I'm following the Getting Started document for Docker, everything works fine except when I run 'sudo apt-get update'.

I get the following error related to 'libcurl':

Protocol "http" not supported or disabled in libcurl

Online searches have not returned anything related to my situation.

Machine: Ubuntu Server 16.04.2 amd64 running in a VirtualBox VM.