Mac migration (or Time Machine) do not work with Cloud program activations due to hidden files
Sign out of your account... Uninstall... run the Cleaner...
-Restart your computer... Sign in to your account... Reinstall
-using the cleaner after uninstalling and before reinstalling may help
-http://helpx.adobe.com/creative-cloud/help/install-apps.html (and uninstall)
Do you mean sign out of my Adobe account on my old computer?
No... the computer to which you migrated
I can't sign in to my Adobe account, because I can't get Creative Cloud to run, so how could I sign out? I have trashed all Adobe files as above, used cleaner on both computers, un-installed and re-installed Creative Cloud and restarted the computer countless times, I still have a grey Cloud icon in my menu bar which when I click on it gives me a blank window with no tabs, no sign in prompt.
After following all advice I could find on here, I solved this after finding some Adobe folders in the utilities sub-folder of my Applications folder and deleting all of them.