Hello!
I don't know how to properly explain what is happening, but Zorin's OS 18.1 Software Store doesn't work properly, this is the second time this happens to me.
I tried to uninstall an app (in this recent case MysticQ Video Converter), and still shows as installed, in the installed list of apps, and there is no way to delete it, this was a Zorin's apt package.
I love Zorion OS, but this annoyance, makes me feel very frustrated.
Please help!
in a terminal type sudo apt purge MysticQ Video Converter
or replace purge with uninstall
Hi!
I already did that, also tried to purge it, and manually deleted all files I could find, but the app still appears in Software Store listed as installed eventhough the app has been deleted using Terminal.
sudo apt remove mystiq
looks like this is way i was close.... 
1 Like
This issue often happens when the program is running in background during the removal.
Install the package again (in the package format it is shown as installed) - for the apt package e.g.
sudo apt install mystiq
and then open it.
Don't close the program by clicking on the close (x) button of the window, because some programs aren't quit this way.
Quit the program via an entry "quit" or similar in the menu of the program or perhaps by right-clicking on the panel icon.
Then remove the program again.
sudo apt remove mystiq
Edit: If it doesn't work and you aren't able to launch mystiq try it with
sudo apt reinstall mystiq
Another way to launch an application is to open a terminal and enter the package name. Closing the terminal will close the application.
You can also check which applications are running through System Monitor on the Processes tab. Rifght-click the offending package and select 'kill (process)'.
The Software is not a Zorin thing, it is a Gnome thing which is buggy. You might want to reinstall it with:
sudo apt reinstall gnome-software
Personally I prefer Apper and Synaptic Package Manager over gnome-software.
Hi!
Thank you so much for the clarification,
I am going to check those package managers.