[FIXED] Random CTDs due to internet and hardware issues

After I’ve managed to setup my system to run Microsoft Flight Simulator 2020 stable and crash-free I started helping out others. In this post I’m giving you insight on how I troubleshot and finally got the stubborn issues out of the way on the PC of my fellow flight sim pilot @EpicPrimus.

EpicPrimus himself desperately tried to solve the issues through various online sources like youtube, guides, forums and Microsoft support, but all efforts were to no avail. I gave him a helping hand and after lots of trial and error we got it working.

His PC is a two months old AMD Ryzen / Nvidia GTX build. See detailed specs below. He bought the Premium Deluxe version of FS on the Microsoft Store.

:eyes: TL;DR

The gist of this post comes down to setting the FlightSimulator.exe process priority to low and changing the process affinity by un-checking the first and eventually second CPU core. Updating windows and its drivers and making sure there are no power-saving modes enabled. Reset of any custom CPU, GPU and RAM overclocking, as well as network adapter (ethernet or wireless) and changing of DNS IPs in router or in windows directly. Don’t forget to restart. For a detailed explanation, please keep on reading. Enjoy!

:video_game: System Specifications

AMD Ryzen 7 3800X
Nvidia GeForce GTX 1660Ti 6GB
G.Skill Trident Z Neo 16GB DDR4
600Watts PSU
Flight Simulator installed on 256GB M.2 SSD
Windows 10 Pro 64Bit

:information_source: Problem description

Starting FS was never an issue. Also changing settings and setting up a flight in the main menu worked fine. The problems appeared after loading into a flight: Stutters, freezes and finally a crash to desktop, occasionally with a blue screen.

Sometimes FS crashed shortly after starting the engine(s), no matter the aircraft, sometimes after a longer flight. In many cases though, FS crashed during airport approach with an active flight plan.

We’re a small FS community performing flights all over the globe. So the issues are not bound to a specific world area or airport.

It’s likely that FS in its current state has problems with so called garbage collection (RAM related, causing lag spikes) and other game engine processes (multithreading, etc.) that make the game become unstable in certain conditions. Asobo / Microsoft is working on a patch, but I managed to get my own copy of FS and others to run nevertheless.

:white_check_mark: Problem solving

After going through the typical steps of updating windows and drivers, we put all FS settings to low and switched off all effects (bloom, ambient occlusion, etc.) including live air traffic, to ensure the lowest possible resource consumption of FS itself and see how the system reacts. Yes, we even turned off force feedback to be really sure all in game performance related settings were low. A couple of test flights concluded that the issues persisted in the same extend. So the journey finding a solution went on.

:arrow_right: Make sure PC is running at its fullest potential
This might seem obvious, but many people have power saving enabled for their CPU and GPU.

In windows open “Power Options” and change the active power plan to “High Performance” or better yet, “Ultimate Performance” when available. To unveil the ultimate performance option, run a command prompt as administrator and enter the following command “powercfg -duplicatescheme e9a42b02-d5df-448d-aa00-03f14749eb61”, reboot and repeat the above steps to change the power plan to Ultimate Performance. This will make Windows prioritize performance over energy efficiency.

Next step is to make the graphics card (GPU) run in its highest performance mode. The following steps are for Nvidia cards. Else search online to find the specific steps for your GPU brand. Open Nvidia Control Panel, click “Manage 3D settings” on the left and open the “Program Settings” tab. Select “Microsoft Flight Simulator (flightsimulator.exe)” from the drop down list. Scroll down to “Power management mode” and set the value to “Prefer maximum performance”. Click apply at the bottom. In case you see the option “Preferred graphics processor for this program” in the list, set it to “High performance Nvidia processor”. Apply and close the program.

:arrow_right: Disable custom overclocking of CPU, GPU and RAM
A little counterintuitive compared to the previous section, but during my tests (on several different systems) I noticed that Microsoft Flight Simulator 2020 absolutely dislikes any custom overclocking whatsoever. Factory overclocked hardware runs fine, it’s the custom settings that made FS crash, no matter the factor the hardware was overclocked with nor the benchmarking results. So in e.g. MSI Afterburner, either stop the program or reset the active profile. Disable XMP for RAM and UEFI CPU auto overclocking features. Basically try to disable any custom overclocking in software, bios and UEFI, and let the hardware run at stock speeds. Also disable any boosters or helpers as they might interfere with FS as well, at least in its current state. This will definitely change with future patches.

:arrow_right: Find error codes with Windows Event Viewer
In order to find information for specific windows errors causing FS to crash, run “eventvwr” and examine the list of errors that is presented to you. Google the error names with their codes to find more information on what they mean and how others solved them. This could be drivers, other programs, Flight Simulator DLLs, or certain hardware failing. All in all this can give a better picture of what makes FS crash. Make sure to use the event viewer right after FS has crashed, else other windows related errors might clutter the list.

:arrow_right: Check DirectX and Microsoft Visual C++ Runtime
Run “dxdiag” and let it analyze your system. Possible hardware issues related with DirectX will be shown here. Also make sure your DirectX version is up-to-date. Next update or refresh your Microsoft Visual C++ packages, as FS depends on these packages in order to run. You’ll find the latest download here: https://support.microsoft.com/en-us/help/2977003/

:arrow_right: Windows 10 Version 2004
Other FS users have reported that after upgrading Windows from 1909 to version 2004 FS and other games started to crash and loads of “Runtime Error 67” errors appeared in the event viewer. If you just updated and have the same issues, you have 10 days to roll back the system (search update on your pc). Else a fresh Windows install is required in order to run the previous version. However, that might be troublesome and worth the wait for a hotfix or keep trying to solve the crashing issue with other steps.

:arrow_right: For the tech savvy: BIOS Upgrade
Check your motherboard manufacturer website to see if there is a BIOS update available for your model. These updates mostly contain performance and stability improving changes. Be careful though, check out online tutorials on how to perform a BIOS update, as this might cause data loss or render your system unusable when carried out wrong.

:arrow_right: Set FlightSimulator.exe Process Affinity
This has definitely made FS run more stable and is easy to perform. But note, this only works for CPUs with more than 4 cores, else this’ll slow down your system. What it does is specify which cores of the CPU may be used by FS. Switching off one or two cores will give back available CPU resources to windows and background tasks, as FS might occupy all cores 100% basically choking windows itself, which may force windows to shutdown FS to prevent a system crash.

Run FS and open the task manager. Switch to the “Details” tab and locate “FlightSimulator.exe”. Right click on the process and choose “Set affinity”. Start by disabling core 0. You may also disable core 1, try it out and see how the system performs. Always make sure to only disable the first (0) and eventually the second (1) core, no more and no other cores.

If this helps you, you might want to start FS with a batch file that automates the affinity change for you. PM me if you need help.

:arrow_right: Set FlightSimulator.exe Process Priority
Like setting the affinity described above, setting the priority works kind of the same way by preventing FS to consume every available CPU resource, thus giving windows and its processes room to breathe, so to speak.

Whilst FS is running, open the task manager. Switch to the “Details” tab and locate “FlightSimulator.exe”. Right click on the process, choose “Set priority” and set it to “Low”. Again, try it out and see how the system performs. You might think, why not set it to high. Well, that would make the situation even worse by giving FS even more priority. That would push aside other processes, raising the risk of a CTD instead of lowering it.

:arrow_right: Change DNS Settings
You can play Microsoft Flight Simulator 2020 all on your own, like offline, but it still requires you to be constantly online, to be able to verify your license, basically checking whether you’re allowed to run the game or not. In cases where the connection is disrupted or lost, FS might simply close. Also the multiplayer experience might suffer from connection issues. One of the possible solutions to this problem is changing the primary and secondary DNS IPs in your router or in the active network adapter settings in windows. The default DNS of your ISP might be slow or unreliable. Personally, I have good experience with the Google DNS. Alternatively Cloudflare DNS is also a good one to try, but there are many more out there. More info on how to set this up and what it is:

:arrow_right: Reset the network adapter
It’s generally a good idea to reset the active network adapter (ethernet / wireless) and the DNS cache from time to time. This resolves connection related issues. In order to do this, open an elevated command prompt (run as administrator) and enter the following commands in order. Restart the pc when done.

ipconfig /flushdns
ipconfig /registerdns
ipconfig /release
ipconfig /renew
netsh winsock reset

:arrow_right: Disable IPv6 and Networking Protocols
If you’re not using IPv6 and don’t rely on communicating with PCs in your local network, you can disable several protocols in the network adapter settings. This will prevent even more possible connection issues during a FS flight.

Right click on the network icon in the taskbar and open the “Network and Sharing Center”. Here click on “Change adapter settings”. Now locate the active network adapter, right click and select “Properties”. Uncheck everything EXCEPT the following and click OK when done:

Client for Microsoft Networks
File and Printer Sharing for Microsoft Networks
Internet Protocol Version 4 (TCP/IPv4)


:point_right: Conclusion

These steps finally made FS run smooth and stable enough to be able to enjoy multiplayer flying together. Of course every PC is different, so are everyone’s personal expectations. Give these steps a try and see for yourself. As soon as your FS runs stable, start tweaking the in-game settings to your liking, whilst keeping an eye on your system stats with e.g. MSI Afterburner, the good old Task Manager or your own favorite toolset. A good FPS counter is the one included with Nvidia GeForce Experience game overlay, which also enables you to record your flights! The FS integrated FPS counter from the developer mode is kinda bulky, but gives you some useful information.

:grey_question::grey_exclamation: Please ask questions by replying to this thread or sending me a PM. I’ll gladly help to also get your Flight Simulator experience up and running!

:eight_pointed_black_star: In case of suggestions, tips, remarks or other solutions that worked for you, let others know as well by posting them below. EpicPrimus and I have created a Community Troubleshooting Guide that we keep expanding with solutions and tweaks. Make sure to check it out as well:


Happy Flying! :grin: :small_airplane:



Patch #1

Patch update coming: “Patch contains fixes to reduce crash and installation issues, along with other bug fixes and improvements.” (August 27th, 2020 Development Update - Microsoft Flight Simulator)
Patch “” is released!

Patch #2

The exact release date is not confirmed yet, but the patch will be released this month. Patch #2 will have an increased focus on the “in-sim” experience. A complete patch list will be published prior to release. For more details, visit the link to the official development update below: September 3rd, 2020 Development Update - Microsoft Flight Simulator
Patch “” is released!

Patch #3

Expect an update on the next patch release on September 24.
Source: September 17th, 2020 Development Update - Microsoft Flight Simulator

World Update I:
September 24th, 2020 Development Update - Microsoft Flight Simulator

Patch “” is released!

Update #4

Release notes: Release Notes ( Now Available! - Microsoft Flight Simulator
Update “” is released!

Update #5

Development Updates:
[BLOG] October 15th, 2020 Development Update
[BLOG] October 22nd, 2020 Development Update
Update #5 Delay - Microsoft Flight Simulator

Update “” is released!

Update #6

Update “” is released!

Update #7

Update “” is released!

Update #8

Update “” is released!

Update #9

Update “” is released!

Update #10 - World Update 3

Development Updates:
- [BLOG] January 21st, 2021 Development Update
- February 11th, 2021 - Development Update - Microsoft Flight Simulator
Update “” is released!

Update #11

Update “” is released!

Update #12

Update “” is released!

Update #13

Update “” is released!
Hotfix available!

Update #14

Update “” is released!


Update #15

Update “” is released!



Microsoft is about to release a patch that contains fixes to reduce crash issues (https://www.flightsimulator.com/august-27th-2020-development-update/).

What is your exact problem? Maybe I can help you till the patch is released. Lemme know.

:wrench: Other useful performance related posts :gear:

      (I’ll keep expanding this list)


:white_check_mark: The new forum changes are live! You can now upvote the reported issues / fixes (left hand side of thread title). Please don’t hesitate to do so on the threads you find helpful. Thanks.


Thank you @AmbitiousPilots for the detailed instructions to try and eliminate my continued CTD events with FS2020.

Using your instructions (reducing all rendering and data feed to their lowest levels, and setting Process Affinity with CPU 0 removed from the stack), I was FINALLY able to execute a brief flight across town (Seattle), and successfully landed at a local airport - this 20 minute flight was the best I could muster since last week when I installed the sim.

However, I thought I’d forward an interesting CTD scenario that now baffles me. When I try and gracefully quit the program altogether (Quit to Desktop), and finally get to the desktop, I open Event Viewer, finding that FlightSimulator.exe actually faulted and showed up as an Application Error (Event 1000) - of course without any indication as to why, other than the normal ‘Faulting application name…’ with all the other non-descriptive logged metadata. Interestingly, I can repro this every time I take a brief flight and close the program.

At least it’s consistent!

I welcome your (or anybody’s) thoughts.

BTW my system specs:
CPU: Intel I7-9700k 3.6GHz (Turbo shut off)
Mobo: Gigabyte Z390 Aorus Pro Wifi
Ram: 32GB - 3200MHz
Video: Nvidia RTX-2070 Super (not overclocked)


1 Like

very interesting post - did the changed the priority using lasso - but the big thing that helped me was changing the virtual memory from 6gb to 8-32gb

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Welcome @DanZ0208 and @mac2244 :wink:

@DanZ0208 , I’m stoked that you’re able to finally take off now by going through the steps in this guide!

Regarding the CTD after gracefully closing FS, the error code is a general one without any specific meaning other than “the application has crashed”. BUT, have a look at the error log again and try to locate “Faulting module path”. It might say “C:\WINDOWS\SYSTEM32\nvwgf2um.dll” or some other file that caused the error. In case it’s the nvwgf2um.dll, you might need to downgrade the Nvidia driver, as this DLL is part of it. Downgrading also helped others in the forums. For me personally, I’m using the 452.06 driver without any issues so far, using FS on a daily basis. Also, the error did not appear in my event viewer logs.

Did you perform the test flights at the same airport / area, or random? Also in what weather conditions did you fly? Multiplayer or solo? Are you running Windows 10 version 2004 or 1909?

Your system specs look great, they should be able to handle FS nicely. We’ll see what the upcoming patch (might be released tomorrow) will change. The 32GB RAM, 8GB VRAM and 8 CPU cores are very close to the ideal Nvidia specs given by Microsoft themselves (https://flightsimulator.zendesk.com/hc/en-us/articles/360013463459-Minimum-Recommended-and-Ideal-PC-Specifications-for-Microsoft-Flight-Simulator).

Let me know your findings with the DLL in the event viewer.

EDIT: I just found, that the error might also be related to the Microsoft Visual C++ Runtime. Did you follow that step in the guide above (Part: Check DirectX and Microsoft Visual C++ Runtime)? Other than downgrading the Nvidia driver, this could fix it as well.

@mac2244, yea that’s what helped @EpicPrimus as well. Did you only use Process Lasso to change the priority? Might be worth a try to use the task manager and also set the CPU affinity as described above in case you’ve got a CPU with more than 4 cores.

Is your FS stable enough now for you to be able to fly?

Whilst you’re at it, in Process Lasso, there is another option that can be disabled to optimize FS performance (see screenshot below, credits @TessellatedGuy):

1 Like

thanks for the reply
1)Running a i7 6700 so i think more than 4 cores - what is the suggestion with the cores and I can try - can you highlight as didn’t see the post?
2)Yes aware of the other lasso tweaks - priority to idle(which means low) and also disabling the dynamic - you also have to set window to priorities background task…
3)tweaks mentioned above seemed to help but i was still getting some CTD - but changing the virtual memory to 8-32gb and I was able to fly for hours with no CTD’s - even across complex cities - so thoughts are this made the biggest improvement…
just FYI running 32gb of memory and a 2080ti - I did try and tweak the graphics settings didnt help - i can get around 30fps on high settings - also tried enabling vsync and this seemed to make the game laggy so running off

  • Your CPU has 4 cores and 8 threads. I’d say try it, when the game runs “slower” don’t use the process affinity tweak, if FS runs better (higher fps, more responsive) use the tweak.

  • A Nvidia RTX 2080 TI should definitely be able to pump out more FPS. Try the following:
    Open Settings -> System -> Display -> Find and click on “Graphic Settings” -> Select “Microsoft Store App” then “Microsoft Flight Simulator” -> Click “Add” -> Click “Options” and select “High performance”. That should force your GPU to work at full potential. Try it out.

Here are some screenshots that depict the steps described above:

(Imagery source: https://www.ucmadscientist.com/stuck-loading-in-flight-simulator-2020/)

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thanks for the reply.
1)firstly my graphics page looks slightly different - maybe because I use win 10 v1909 - decided not to update yet as the latest version seems to be creating some issues for other users
2)I think all you are doing in the above is setting the performance mode for the graphics card - note my 2080ti is ROG which comes with its own software so you can set it to gaming or manually OC - which I already do
3)interested to try the affinity tweak - how do you run this? (assume its via lasso)

Yes, stay with Windows version 1909 for now, as it’s the most stable release at the moment, regarding FS2020.

Here are the steps for the affinity tweak:
Run FS and open the task manager (ctrl+alt+del). Switch to the “Details” tab and locate “FlightSimulator.exe”. You can also use Process Lasso for this. Right click on the process and choose “Set affinity”. Start by disabling core 0. Try it out and see how the system performs. Always make sure to only disable the first (0) and eventually the second (1) core, no more and no other cores.

What it does is specify which cores of the CPU may be used by FS. Switching off one or two cores will give back available CPU resources to windows and background tasks, as FS might occupy all cores 100% basically choking windows itself, which may force windows to shutdown FS to prevent a system crash.

Regarding your graphics card:
You can also set the power mode in the Nvidia Control Panel. To do this, open Nvidia Control Panel, click “Manage 3D settings” on the left and open the “Program Settings” tab. Select “Microsoft Flight Simulator (flightsimulator.exe)” from the drop down list. Scroll down to “Power management mode” and set the value to “Prefer maximum performance”. Click apply at the bottom. In case you see the option “Preferred graphics processor for this program” in the list, set it to “High performance Nvidia processor”. Click “Apply” at the bottom.

Whilst you’re in that window, locate “Max Frame Rate” and set it to “30”. People report a more stable FS and fewer crashes with that setting. Again, click “Apply” at the bottom and close the program.

Let us know how it worked out for you :wink:

Hi, Someone have any idea about that? tks

1 Like

Maybe the level of detail for objects? Should he one of the sliders.

Happy landings!

First of all, the screenshot you compare your scenery to is from the alpha stage of the game which changed before release.

Furthermore, try the “Ultra” preset in your settings or change “Buildings”, “Texture Resolution” and “Texture Synthesis” to Ultra and make sure both “Terrain Level of Detail” and “Objects Level of Detail” are set to 200. This ensures FS2020 will render its environment with the highest quality the game engine has to offer.

However, this may be very taxing for your system, depending on your specs. Give it a try and update us with some screenshots when you feel like it :wink:

Ladies and gentlemen,

IT’S TIME TO UPDATE :star_struck:

Patch Version has been released and is available for download!

Update FS in the windows store first then start it. Steam users simply start FS and the update will be downloaded.

Please find the patch notes here:

I’m flying Live multiplayer with windows 10, 2004
The event viewer faulting module path is:

The event viewer faulting application path is:

I just started noticing that I have been flying jets when the crashes are happening and some airliners with both low FPS. Yesterday, I tried some general aviation planes and the FPS was 60+, sometimes spiking past 100. It could be the way the Jets and Airliners are model that are causing low FPS and desktop crashes.
I tried fly the B747 from KLAX to KSAN with low FPS yesterday and the FMC did not want to follow the flight plan. The plane flew in the opposite direction of KSAN and I had to fly manual all the way to KSAN. And I notice that there is no direct-to on the FMC. Or I couldn’t find it! And I could not input a new waypoint when directed by ATC.

Hi @AmbitiousPilots - nothing in the Event Logs pointed to a suspect DLL. All I saw were the suspect ‘Faulting ProcessID’ and other data that referenced my specific install of the app.

I’m also sad to say that I was forced to rebuild my PC from the ground up!
After trying to update the VS C++ Redistributables and restart FS, it said I needed to install the (Aug27) updates before I could fly - yes my timing is impeccable! UGH!!
Installing the updates then gave me an error that my SSD did not have the capacity for the entire install (100+ GB). UGH! So, I decided to uninstall and attempt to re-install FS. BIG MISTAKE! Re-installing FS from the MS Store crashed my PC and forced-rebooted every time! I ended up rebuilding Windows from a fresh USB stick - hopefully I can bring things back up to a workable state. UGH!!

I’ll reply back in a day or so and let y’all know what I did to fix things.

This is a BIZARRE experience!

Oh - and I was also able to revert back to Win10-1909, which might increase my chances of having a GREAT flight in the near future :slight_smile:

Hi @ChrisofUSA7229, the bigger aircraft are indeed requiring more resources as they’re more complex, mainly the cockpit instruments.

What you can try is a community fix that lowers the “refresh rate” of these cockpit instruments, which should help increase FPS and lower the amount of work the CPU has to cope with every second.

Here’s how to:

  1. Download this zip file and extract to e.g. your desktop:
  2. Copy the folder called “FPS-Fix-15Hz” to the FS2020 community directory.
    To find this directory, enable “Developer Mode” in the general game settings. In the dev menu at the top of your screen, click on Tools and select “Virtual File System”. Expand “Watched Bases” and note down the path containing “\Community”.
  3. Run FS2020 and start a flight with an airliner.

Credits for this fix:



@DanZ0208 that’s very weird that the re-install of FS messed up your OS. Personally, I think there was something else that got corrupted which prevented it from running. That’s one reason I’m using a separate SSD partition running a separate Windows installation for my games.

Did you try to run Windows in safe mode or use any recovery method before rebuilding? Because it’s unlikely that the update of the C++ Redistributables, the Windows Update and FS re-install would’ve caused so much damage, that’d have rendered Windows unrecoverable. I hope you’ve made some backups of important data. In case you didn’t, I recommend you start doing so.

Anyhow, it’s indeed sad to hear this happened to you. But the good thing is you’re running a fresh Windows with version 1909 now, which should be the more stable one for FS.

Keep us updated. Questions are welcome any time!


You do not have a clue, what You are talking about. Do not write nonsense like this before checking the complete truth of Your sayings.

The patch gave me 10fps more by fixing the somconnect issues.


:hammer_and_wrench: The development update of September 3rd states, that  patch #2 will be released this month  focusing on the simulation experience itself. Sounds promising! Check out the following link for more details: