I don't normally answer forum questions since they're usually from people that fail to RTFM.... but I sympathize for you because Flash player is so widely required but also so terribly vexing if it breaks.

Your steps to solving type of problem should first to completely remove Flash and that is easier said than done. Adobe's web site has a less oft used page that describes how to do so at:

http://helpx.adobe.com/flash-player/kb/uninstall-flash-player-windows.html

Then, reinstall Flash.

If that still fails, plan to repeat the process of removing Flash and completely uninstall Firefox.

Reinstall FF and immediately reinstall just Flash before restoring your old bookmakrs and add ons.

Test those sites and functions that are currently nonworking for you at the moment to determine if your FF and Flash are working again.

If so, then systematically reinstall your addons taking great care to retest sites before just reinstalling every add on since it may just reinstall your incompatibilities and problems.

Firefox doesn't use the ActiveX Flash version.
Firefox needs its own version of the Flash plugin.

• http://www.adobe.com/software/flash/about/
• http://helpx.adobe.com/flash-player.html

A possible cause is security software (firewall,anti-virus) that blocks or restricts Firefox or the plugin-container process without informing you, possibly after detecting changes (update) to the Firefox program.

Remove all rules for Firefox and the plugin-container from the permissions list in the firewall and let your firewall ask again for permission to get full unrestricted access to internet for Firefox and the plugin-container process and the updater process.

See:

• https://support.mozilla.org/kb/Server+not+found
• https://support.mozilla.org/kb/Firewalls

Thank you so much for responding to my question right away! You really helped me out. I've been so swamped in my school work and job I haven't had time to do anything else. Thanks alot for giving me a fast, straight to the point answer :) my problem is solved!