hello, could you go to the firefox menu ≡ > help ? > troubleshooting information, copy the contents of that page and paste them here into a reply on the forum? this might give us a clue what is going on...

If you visit the following page and activate Flash using the plugin notification icon on the main toolbar (to the left of the site address, looks like a small dark gray Lego block), does it mention needing an update or does it say you're already up-to-date?

https://helpx.adobe.com/flash-player.html

Unrelated to the Flash problem, your Adobe Acrobat plugin is very out-of-date, which probably means your Adobe Reader/Adobe Acrobat also is out of date.

In Reader/Acrobat, you should be able to use the Help menu, "Check for Updates" to get the 10.1.16 release, which was the last in the series for Adobe Reader/Acrobat X.

If that doesn't work, there are some huge downloads still available on Adobe's FTP server here:

• Reader on Windows: ftp://ftp.adobe.com/pub/adobe/reader/win/10.x/10.1.16/
• Reader on Mac: ftp://ftp.adobe.com/pub/adobe/reader/mac/10.x/10.1.16/
• Acrobat on Windows: ftp://ftp.adobe.com/pub/adobe/acrobat/win/10.x/10.1.16/
• Acrobat on Mac: ftp://ftp.adobe.com/pub/adobe/acrobat/mac/10.x/10.1.16/

Have Firefox 49.0..... Cannot select "Ask to Activate". On anything. Cannot deselect "Auto Play" on useless ads. Firefox constantly hangs-up. Selecting "Check for Updates" reveals nothing "out-of-date". This is frustrating.

Hi hawkeyeswa, is this a continuation of your question from a couple weeks ago? We should continue there rather than using someone else's question:

https://support.mozilla.org/questions/1138308