How do I get rid of greatis software-RegRun?

Hello Sandy.
Regarding the issue that you face, I have sent you an email to make the resolution easy for you. I request you to check your inbox and you will be good to go.
Thank you.

I just got this computer back from the shop.  Now I have this stupid program RegRun Partizan by Greatis software.  I have uninstalled the program but it still comes up.  I manually edited my registry to get rid of all references to this software, but it still starts on boot.  I cannot find any trace of it, but it still is there.  In my opinion, this is a breach and I feel hacked.  It does something with the rootkit.  Anyone know how to get rid of this pest?

Hello Sandy.
Regarding the issue that you face, I have sent you an email to make the resolution easy for you. I request you to check your inbox and you will be good to go.
Thank you.