apt-get install ssh openssh-server

I selected ssh on the initial ubuntu screen of programs to install and I also ran the above command after ubuntu was installed as recommended by this doc. Afterward i tried logging in using putty. I got 'connection refused error'.

I then looked elsewhere for help and found this command

apt-get install openssh-server

 After i ran this i was able to connect using putty. Command is only different than the other one by 'ssh'. Not sure why this works, but it works now.