Have tried to upgrade (performed all the steps for a clean install including running uninstall app).
When it gets to the screen to select via radio buttons how you want future updates to be installed (notified, auto, manual, etc), no other selections can be made and the install locks.
Download the offline istaller: Flash Player 126.96.36.199 (Mac OS X)
DON'T run the installer from the GUI.
When it opens, right click the installer and "Show Package Contents"
In Contents/Resources, double click the Adobe Flash Player.pkg
and run the COCOA installer.
Same result, just a different way to get there.
Doesn't work, says I'm not authorized even though I have adminstrative access through the normal sharing. May work if logged on as a root user.
I've tried all the suggestions in all these posts. Seems like Adobe messed this up pretty good, don't like how they can just disable the current flash. More reason to get rid of flash altogether ....
OK, so my problem is different that some, somehow running the flash player installer locked me out of administrator access. the symptom is when clciking the install button, rather than getting the authorization dialog, the button would sort of flash but nothing at all would happen. I went to the users and groups preferences, but clicking the lock icon did nothing. Somehow I as locked out. Not sure what did this.
I downloaded the stand alone installer as mentioned in some threads, rebooted my Mac Pro (2013, OS X 10.9.1), ran that installer and now things are working.