Administrative Remote Desktop: My computer connected with family member

[Sophie]

A family member who I trusted activated his Administrative Remote Desktop five years ago. He passed away that same year and his computer ended up in his friend's possession. I believe that (the friend) is connected to my computer by ARD.
Is it possible that he is hidden from me by way of curtain mode so I have no proof of his presence - the binoculars in the title bar are absent. If this is true, could he be controlling and making changes that I know I didn't? Is there any way for me to disconnect him from my computer? In 2011 I bought this computer thinking that would work, but it didn't happen. I have tried to no success and am very stressed.

 

[Cory Cooper]

Hello and welcome.

The only way a Mac can be accessed via Remote Desktop is with a user name and password. If they are using curtain mode, your screen would be covered with a "curtain" and you wouldn't be able to see your desktop/use your Mac, as shown below:

-Did you give them your account's password? If so, change it.
-Do they have an account on your Mac? If so, delete it.

You should also simply turn off the following in  > System Preferences... > Sharing
-Remote Login
-Remote Management
-Remote Apple Events

If those services are off (unchecked) then you should be safe.

C

 

[Sophie]

Your questions above: All have been taken care of. Perhaps another software application is being used instead of ARD? As I had mentioned earlier, I have had five years of experiencing so many unanswered questions. I know that it is not just in my head; there is so much truth to this mystery to deny. I am not very tech savvy but; I try my best.
I thank you Cory for your help!!

 

[Cory Cooper]

That's a good start. We are more than happy to continue the investigation with you. Any third-party applications that can access your Mac remotely will reside in your Applications folder and/or have a Preference pane in System Preferences and would need to be running to enable access.

Feel free to ask away regarding an unanswered questions you may have.

C