Download the ScreenConnect PKG file from the link provided to you by iion. If you have not been provided a download link, you can click the generic installer below:
https://iion.screenconnect.com/Bin/ScreenConnect.ClientSetup.pkg?e=Access&y=Guest
Note: the instructions below may reference ScreenConnect or ConnectWise Control. Both are interchangable (the software now known as ScreenConnect was previously named ConnectWise Control)
Once the file has been downloaded, open Finder and navigate to where the file has been downloaded. Usually this is your Downloads folder.
Identify the ScreenConnect.ClientSetup file.
Note the file name may have your company name appended to the end.

After double clicking, the below prompt will appear. Do not be concerned about this – it’s expected. Click on OK to continue.

On the top left-hand corner of your screen, click on the Apple icon, then click on System Preferences.

From the System Preferences menu, click on Security and Privacy.

On the General tab, click on Open Anyway