corrupted Flash uninstall file

If the file is corrupted, something underneath us isn't working right (e.g. the filesystem is corrupt, or the hard disk is flaky, some underlying driver/hardware component is in a bad state, etc.)

Here's what I'd recommend: 

1.) When in doubt, reboot.  Actually power the thing off.  Give it ~30 seconds to let all of the hardware fully discharge, then start it back up.  This might not fix it, but it removed a huge number of possible problems from the equation.

2.) Download and run our uninstaller for Mac: 
https://helpx.adobe.com/flash-player/kb/uninstall-flash-player-mac-os.html

If that doesn't work, try running Disk First Aid to identify and repair any underlying issues.  If you don't have a working backup that you're confident you can restore from, deal with that first.  If your disk is dying (particually if it's not an SSD), running a comprehensive disk scan is going to give it a good workout, and may push it over the edge.  It's wise to back up anything critical while you have access to it.  Disk recovery services are expensive.

If you're still stuck, let us know.  We'll collect some logs to identify the reason that it's failing and try to give you more tailored advice.