What happens if you unpin the pinned Firefox (the one on the left) and then repin the unpinned one (the one on the right)? Does this fix the problem?

ok that fixed it... which is weird cause I unpinned it and restored from program files list w/o this correction. Thanks a million

Since the update to 9.0.1 even if I unpin the old icon it doesn't help. The new icon that appears on the far right doesn't give me the option to pin it. And if I go to my start menu and pin that version of FF, when I open a new session the new icon appears on the far right, and the pinned version doesn't show as active.

Seems to be a problem ever since 9.0.1, as it worked correctly for me yesterday. I thought at first that the FF browser had crashed, as the pinned icon lit up when FF was started, then faded. Any minimised windows weren't visible through my pinned icon. I have a lot of pinned icons, going across two monitors, as a result, it took me a long time to see the new FF icon on the far right, which was showing more or less correctly - Except you can't pin that one, you don't get the option when you right-click on it.

I guess my next step is to reinstall and pray it works, or move to a different browser, which I really REALLY don't want to do. I've been using Mozilla products since Netscape 0.99a (!!!) back in 1994!

Thanks - unpinning the original icon from the taskbar and repinning from the start menu does not work. I tried that on 2 different computers. However after unpinning I then used your suggestion to pin from the opened icon (right click on the icon and choose "Pin This Icon To The Taskbar") and for some reason that DOES work..

I really needed this as it was interfering badly with my productivity. And just as well I found the answer as I was about to download Chrome!