After getting Creative Cloud a couple of days ago then running into Updater Error U44M1l210 over and over and making the mistake of calling tech support (which was no help - "just reset it / download from the site" - even though resetting does nothing and the site doesn't have all the updates AAM does), I've finally got a working solution.
Essentially it's a permissions issue. Not sure why it affects some and not others, but I was logged in as an administrator and it still failed to have permissions to update despite admin password entry.
So, here's what you do. You need to open AAM and Update with superuser permissions.
1. Open Terminal
2. Copy and Paste the following, then hit enter:
sudo "/Library/Application Support/Adobe/OOBE/PDApp/core/Adobe Application Manager.app/Contents/MacOS/PDApp"
3. It will prompt you for your password, enter it.
4. The Adobe Application Manager will open with sudo (elevated/superuser) permissions.
5. Open one of your Creative Cloud programs.
6. Go to Help>Update...
7. The updater dialog will open. Update as normal, it will work this time.