Problems with uploading pictures on Facebook.

This is a known problem with Internet Explorer 11, which Microsoft has been aware of since October 18 when they released their latest "untested" browser. The pages can't recognize the browser, so they don't recognize any of the plugins, like Flash Player. So far, Microsoft has made NO indication that they have any plan to fix it soon.
Microsoft's recommendation is to use Compatibility View for affected pages, and "pretend" you're using an different browser. Trouble with that is it has seen limited success at best, and you have to individually enable it for EVERY page that has problems.
I'm not big on "pretending" so I recommend actually using another browser.

Firefox (from Mozilla)

Opera (from Opera)

Safari (from Apple)

Chrome (from Google)

ANY of those will work where IE11 won't, with the Flash Player Plug-in (For all other browsers), and Chrome doesn't even need that because it has its own Flash Player plugin built in.

I think Internet Explorer 11 has been reported by those in the know in this forum as being the problem area. Maybe try another browser although I don't think Adobe can be completely absolved from blame. The amount of issues with flash has increased dramtically. Version 11.9 is giving an awful lot of grief. Maybe uninstall it and try an earlier trouble free version like 11.5