Turning off real time protection and allowing the program under private networks in the firewall pop-up worked for me as well. Afterward I was able to turn the real time protection back on and everything still works now.
I just restored to a restore point from Nov 1, which fixed the problem for me. All I remember installing since then was MS updates.
I was very lazy using restore points over the last year. I’ll pay much more attention after this experience.
Well I first found the firewall box and ticked all mentions of the sim. That made no difference (only box not ticked was public network - not on one - desktop - won’t be ever) Then I made the mistake of trying to delete FS from the permissions and reboot, then try to add it again. I can’t because it doesn’t ‘find’ it and wants me to manually enter location of .exe file: a long path is shown in icon properties but can’t scroll to see it all, hunted through files/folders - found all else except.
Anyway someone here says startup was finally screwed up because of an X-Box update. Oh for a more accesable version of Windows that ain’t linked to a game console.
How do you do that? I’m computer illiterate
You click the windows start button and type “create a restore point”. Then in the System Restore window under the System Protection Tab, click System Restore… If you have any Restore Points, windows will suggest one, or you can choose another one under Choose a different restore point.
It all depends if YOU manually, or Windows automatically have created any restore points. I think windows creates restore points on some or all windows updates (not sure). I was lucky that I had one restore point windows created a few days back. I will definitely pay more attention to creating manual ones in the future.
Thanks. Will try that tomorrow
Well I tried both X-Box networking - said problems - tried ‘repair’ - said no probs. Then after still no load past Mt Fuji screen i switched off real time protection - still now’t. task manager shows 30 to 37 % GPU use just alternating. Its trying something but ain’t getting anywhere.
There have been 2 Windows Defender updates since Tuesday morning (EST).
I have installed both and still no joy… MSFS keeps closing down @ launch.
My strong suspicion still points towards yesterdays update of Gaming Services from the MS Store.
I’m going to hold tight and not mess around with any temporary “hot-fixes”. Hopefully MS will sort the problem and release an update to Gaming Services in the next couple of days.
In the meantime, if I want to go flying, I can temporarily disable Windows Defender - which seems to work for me.
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Worked for me earlier today, but now even with disabled anti virus it wont start again, acting up…great.
Same, it was already excluded before but happend again and now it had a firewall popup. No idea what is going on. Excluded again and now it starts.
same problem here, since the xbox gaming service update yesterday the game won’t go beyond the black startup screen (closes after aprox 4sec.) Though i disabled systemrollback i can’t go for “before” the update, which means, i pretty much have to wait for a fix… thanks.
I am back working as before. This is what I have done to solve the problem.
Disabled Defender as suggested above.
Launch MSFS. (See Note) 
Did a short flight.
Closed MSFS.
Enabled Defender.
Started MSFS
--------------(Note: I am not sure where this next step was. Either last one here or up at the arrow.)
Clicked “Allow” on the firewall pop-up warning.
As a former Security Product manager at a financial organization I think it is absurd that you have to disable the Realtime protection of your Anti virus software to be able to launch your flightsim. Come on Microsoft fix this with High Priority! When I disable my Virus protection my flight sim starts. It is a something to be embarrassed about Microsoft. Fix this please immediately! The devs at Asobo should not be blamed about this!
6 Likes
@ChillM2 I had this issue monday for me i checked in the microsoft store in my library and found that the digital ownership for the flightsim had become uninstalled somehow and said I could install it so I did, then it worked after that might be worth checking yours.
Same here, engine didn’t starting up. Maybe file starvation. Or the code got an infectious disease… 
Or the AI got self-aware…
Story of my life.
FS started fine 12 hours ago; now can’t start. This happens on the first black screen:
What on Earth is going on? What a FIASCO !
I switched Real-time protection OFF, it starts, but I got this now!!!
I clicked Allow access. But I don’t have a
E:3\flightsimulator.exe !!!
The Crazy thing is that there was already, ticked for both private and public in Defender firewall:
With the Allow above, I now have:
and many Disk 3/4 surprised removed!!
with many
Earlier, when FS crashed, I had this:
Now I get this, but there is no Log in feature: What is going on?
I re-enabled Real-time protection
and now FS starts as normal:
Since re-enabling Real-time protection, I re-started then closed, then restarted then closed then re-started FS and it works as normal. So, now FS started 3 times with Real-time protection ON.
So, it seems FS was like a virus : it needed once to start without Real-time protection!!!
and finally, the Microsoft website decided to behave!
Obviously, I just VOTED !
1 Like
Worked for me this morning before Gaming Services update, as well. Now not launching. Will files report.
It does not work for me. Defender stopped. I have karspersky and even if I stop it, it still doesn’t work.
Yesterday it worked for me and today nothing.
