Why does the "OSX Updates Available" come up and when I go to the App Store it says "No Updates Available"?
Because it is a glitch, or more precisely a bug in AppStore.
It's been reported but the more who report the more likely it will get fixed.
You can file feedback here.
App Store – Hide Updates
This helped me:
The app took a thourough look at the updates and finally found some
Is it possible you're not running as an admin user?
I have never run this with admin rights, just as a plain user - and it works, again. IMHO that's not necessary.
You will always be asked for admin rights when an update of system software is available.
Totally agree. It's a bug, but if I fast-user-switch to an admin on some of my computers, the updates are there.
This fixed it for me thanks Robert. It started asking for an admin account again, which is what I expected.
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