Recently after performing a PC clean up routine, the same thing happened to me.  Luckily, most of what I cleaned up was in the recycle bin, so I restored everything snf MSFS restarted fine with all settings intact.  Maybe it was co- incience, but now I have restored a ton of stuff and am not sure which file might have been the culprit.  Thank heavens I didn't empty the recycle bin afterwards.

This goes down as Asobo's biggest 'word not allowed' up since MSFS's inception.

When this happens you should alt f4 or close it with task manager and restart the pc, settings usually come back 

It now reinstalls all those God awful Aviator club etc liveries and reinstalled everything I've just deleted! YOU WILL HAVE EVERYTHING WE THROW AT YOU!

1 hour ago, Ron Attwood said:

It now reinstalls all those God awful Aviator club etc liveries and reinstalled everything I've just deleted! YOU WILL HAVE EVERYTHING WE THROW AT YOU!

Had the same. Terrible experience. Never had this before since msfs release. 

7 hours ago, DAD said:

lucky you. this whole sh... hit me now as well. had yesterday two separate 2GB updates (MS STore and in-game) and today MSFS fully reset. signing out and in XBOX did not help, neither. everytime starts with the accessibility screen. what a f...

Had another 4GB download or so, it even (re)installed all my asobo airports which I deleted because I bought 3PD airports...

It is a MASSIVE mess on MS's part, and they must look at alternatives for storing user data for FS24.

I've been having a never ending cycling of 'updating' reassigning stuff. I've NEVER had such a &*%^$O)(^$%% since I started using MSFS from day one. Who is running this show?

6 hours ago, FormulaJet said:

usually

Hah!

word not allowed, I'm seething!

My 67GB forced Update (February 21, 2024) turned out to be only 45GB (my original post):
https://www.avsim.com/forums/topic/642468-6776gb-msfs-update/

My 2nd PC with MSFS2020 running did not get any forced update (yet).

Luckly, most of my profiles were set up with FSUIPC and they were ok.

Setups that used the default e.g. Thrustmaster Joystick/Throttles needed re-doing.


It took about 30 minutes to install the 45GB update.
That update reinstalled all the default aircraft/airports/liveries etc.
It took about an hour to delete all that unwanted stuff again.

Now a couple more hours retesting aircraft and re-configuring.

Note:
I did a MSFS Support Ticket and the verdict was: 
It must have been a glitch.

After a "round the world" trip with 125 flights the day before yesterday I returned home without encountering any problems when starting the simulator but yesterday this problem arose which was linked to the "disappearance" of the "Data Synchronization in progress" when starting the simulator with the page asking me to reinstall 30 GB which then became 16 GB upon download and after redoing the configuration, as if it were the first time I had installed it, I could fly regularly.

I thought I had solved it but after returning to the desktop, every time I started it the "data synchronization" continued to fail, and I had to redo the configuration again as if it were the first time I installed it if I wanted to play.

After many attempts the Data Synchronization returned, and it started normally with my configuration only when, instead of start it by clicking as administrator on the desktop icon which I believe launches the game from C:\XboxGames, I launched it from the " Xbox app" .

After everything started working normally again by starting it from the Xbox app, I tried many times, between yesterday and today, to start it as administrator from the icon on the desktop and the writing "Data synchronization in progress" always appears regularly and then everything works normally as it worked before.
 

about to reinstall. MSFS does not help. tried to repair MSFS via apps menu. No cure. will skip resetting as then I can re-install anyway. what bother me most is that if my cloud profile got corrupted then all settings incl log data are lost. what a f...reaking mess

35 minutes ago, DAD said:

about to reinstall. MSFS does not help. tried to repair MSFS via apps menu. No cure. will skip resetting as then I can re-install anyway. what bother me most is that if my cloud profile got corrupted then all settings incl log data are lost. what a f...reaking mess

Did you submit a Support Ticket to MSFS2020 to see what they say about the problem?

 

1 hour ago, vonmar said:

Did you submit a Support Ticket to MSFS2020 to see what they say about the problem?

 

did. nothing but signing in/out and how to delete my cloud profile (which will definitely reset my flight log and controller settings)

I woke up this morning, turned on my PC, launched MSFS and lo and behold IT WORKED as it should. setting all in order. I can only assume the it couldn't connect to the Cloud and so kept trying to update and basically got it's knickers in an almighty twist.

Peace and tranquillity has resumed. 😎 Hallelujah