I haven't played Flight for 3 years or more.  Recently I started it back up and noticed that my pilot profile is still in tack as far as I can tell, as are awards and achievements (all completed), but the bad thing is that the missions and challenges, to which I had completed them all and I think I even had all gold on them are now reset and locked like I'm a new user.  I had spent many frustrating hours getting gold on all those challenges and missions and now I have to do several again just to have the more difficult ones unlocked and available.  Anyone know a workaround to unlock them all?  I'm not using FlightToolkit, just standard GFWL in my old account.  FYI I have Hawaii, Alaska, and several planes I purchased in 2012 still available

I don't have a solution but thought I'd commiserate, or join your question.  I too completed all challenges, missions and aerocaches and lost the lot. I am using stonelance's awesome toolkit though. I was originally running GFWL.

I had a moment of silence and moved on. Unfortunately many missions and newly added job types remain locked because of my (current) lack of progress.  You definitely want to install the FlightToolkit and enjoy imported MS FlightSim world scenery, new aircraft and job types.

Perhaps someone else can comment if it is possible to recover your progress, or at least cheat and unlock things that otherwise require many hours of repeated play.

Unfortunately we never added the ability to save mission progress (including challenges) to your player profile.  If you have Flight on a new PC without manually backing up your playerp rofile files, then you will lose progress on those.  It should still remember your stats, like flight time, experience points, aerocaches, etc.  I think they ended up taking down the aerocache servers though, so that progress may be gone as well.  All that data is stored in encrypted files to prevent cheating, so you can't manually change them.  Using Non-GFWL mode it ends up saving all that data locally.  There was a period of time when the MS aerocache servers were still up where I could make a copy of that data to a local profile, but if you didn't log in with the toolkit during that period, or have since deleted the player profile files then they will be gone.  In Non-GFWL that is all just saved into an xml file in the player profile directory (I think %localappdata%\Microsoft\Flight\Players\<some random code>\ProfileData.xml  You could modify it to manually add mission completion, but I don't remember the details.