Errors When Upgrading Ubuntu from 16.10 (Yakkety) to 18.04 (Bionic)

I had an old virtual machine that I wanted to upgrade from 16.10 to 18.04

Since Yakkety (16.10) is no longer supported I followed this guide and updated my source list:

I then did the standard commands to upgrade:

However I got this following error after “apt upgrade”:

To fix this I did the following:

Then did the upgrade again:

Success !