Since the message says you have an old version of KFLL, the solution is of course downloading the current version of KFLL and installing it.
The message appeared after installing KLAX, since it downloaded the sceneries updates list from the internet when you ran its installer and surely the KFLL version you had was before KFLL was updated, that's why you got the alert.
So I uninstalled KFLL, remove it from my scenery list and restarted FS9, but no luck, I am still getting this error message
Something is not correct here because, if you uninstalled KFLL in the proper way (from the Windows Control Panel Add/Remove Programs), there shouldn't be any need to remove it from the Scenery Library manually, since the Uninstaller does it automatically.
Also, you shouldn't get the "old scenery" message after having uninstalled it, which means it hasn't been really removed. Are you sure you have only one FS9 installation on your system, and there's no FS9\Fsdreamteam\KFLL folder left ?
Also, note that FS9 when ran under Vista or Windows 7, might use different scenery.cfg depending if you run it as Administrator or not so, you might have two copies of the scenery.cfg, but only one was updated when removing the scenery manually, which is why is usually best to leave it to our Uninstaller, since it will update both copies.
Try to download the current KFLL installer, install it and, if you are not interested in it, Uninstall it from the Control Panel.