1) Uninstall all the Adobe Apps from your computer including the "Adobe Creative Cloud" App, restart the computer.
Windows 10: Start Menu, Settings (Gear icon), Apps or Right click to the Start Menu , then "Apps and Features"
Windows 7: Start Menu, Control Panel, Uninstall a program
2) Install the Markham College ITC Tool, click here to download, open the downloaded file and run the installer "setup"
Click "Yes" on the "Do you want to allow this app from an unknown publisher to make changes to your device?" dialog. (If appears)
When the installer appears, click on "Extract", when the installer ends, it will close.
Now, you can run the "Markham College ITC Tool"
Click "Yes" on the "Do you want to allow this app to make changes to your device?" dialog. (If appears)
Then the program ends, the computer will restart.
3) Now, you can install the Adobe Creative Cloud 2020 from the previous page