Comment 10 for bug 1722615

I still use synaptic to manage packages because of its simplicity and zulucrypt packages you most likely have installed are those highlighted in the below image:

https://imgur.com/a/jFezM

I also suggest you use synaptic because doing stuff on the terminal is not very user friendly.

1. Install synaptic with command: sudo apt-get install synaptic
2. Temporarily allow GUI programs to run privileged with command: xhost +local:
3. Run synaptic with command: sudo synaptic
4. Search for package "zuluCrypt"
5. Remove all installed packages you see. Installed packages will be green highlighted.

In any of the above commands,if you get a "could not acquire lock error", keep trying to run the command on 2 seconds interval until it succeeds.