Fix FSX freezing on exit by isolating add-on modules, gauges, external utilities, corrupt settings and blocked file writes in boxed and Steam editions.
FSX usually freezes on exit because an add-on module, gauge, weather engine or external utility fails to release cleanly as the simulator shuts down. Corrupt settings, blocked file writes and Windows compatibility faults can cause the same symptom. Test a default flight, then disable add-ons methodically until FSX closes normally.
This applies to both boxed FSX and FSX: Steam Edition. A brief Not Responding state does not always mean FSX has locked up: it may still be closing SimConnect clients or writing configuration and logbook data.
How can I tell whether FSX is actually hung?
FSX is genuinely hung when its window stops responding and fsx.exe remains in Task Manager without completing shutdown. Allow it to finish once; use End task only when it is clearly making no progress, because forced exits can prevent settings or logbook data from being saved.
| Where FSX stops | Most likely cause | Best first test |
|---|---|---|
| Exiting from the Free Flight screen before loading a flight | Global add-on module, startup utility or corrupt configuration | Disable dll.xml and exe.xml, then regenerate fsx.cfg |
| Selecting End Flight after using one aircraft | Aircraft gauge, aircraft-specific module or damaged logbook | Repeat the flight with a stock aircraft |
| After using live weather, AI traffic or hardware panels | External SimConnect client or companion utility | Run FSX without those utilities |
The window closes but fsx.exe remains | Module, driver or external utility failing to disconnect | Remove global modules and specialist hardware software from the test |
| After repeatedly opening the menu bar | Possible UIAutomationCore menu fault | Use the menu-specific diagnosis described below |
A clean add-on isolation test
A no-flight exit followed by a stock-aircraft test separates global shutdown faults from aircraft, scenery and weather problems.
- Restart Windows first. This clears any orphaned
fsx.exe, SimConnect clients or panel utilities left by the previous forced shutdown. - Exit without starting a flight. Open FSX, remain on the Free Flight screen and close the simulator. A lock-up here points towards a global module, utility or profile file rather than an aircraft gauge.
- Run a stock flight. Use a default Cessna 172, a stock airport and default weather. Temporarily turn off add-on weather and AI traffic, end the flight, then exit FSX.
- Remove external clients. Close weather engines, traffic injectors, flight trackers, voice tools and hardware-panel software before launching FSX. If shutdown now works, restore one utility per test.
- Bypass add-on module lists. With FSX closed, back up and rename
dll.xmlandexe.xml. They are normally under%APPDATA%\Microsoft\FSX\; Steam Edition may use%APPDATA%\Microsoft\FSX-SE\, particularly when installed alongside boxed FSX. Skip any file that is not present. - Restore components selectively. If renaming the XML files fixes the freeze, restore one file at a time. Then disable or restore individual entries until the failing module or automatically launched utility is identified. Preserve valid XML structure and keep the backups.
If only one aircraft causes the lock-up, concentrate on its panel gauges and supporting modules. If it occurs at one airport, test without that scenery and its associated traffic package. A failure tied to live weather points towards the weather client rather than FSX itself.
Resetting FSX profile files
A fresh fsx.cfg can fix an exit freeze caused by damaged settings or obsolete add-on entries.
- Close FSX completely and confirm that
fsx.exeis absent from Task Manager. - Back up the configuration by renaming
fsx.cfgtofsx.cfg.oldin the applicableFSXorFSX-SEAppData folder. - Start FSX and exit it once before restoring any tweaks. FSX will generate a clean configuration file.
- Reapply settings manually if shutdown now works. Copying the entire old configuration back also restores the fault.
This reset changes simulator and display preferences, so record any customised settings first. If it makes no difference, close FSX and restore the backed-up file.
Could Logbook.BIN cause the exit lock-up?
A corrupt Logbook.BIN can make FSX stall when End Flight updates the pilot logbook. This is more likely when the freeze happens after completing a flight but not when closing directly from the opening screen.
Back up and rename Logbook.BIN in the Flight Simulator X files folder under Documents, then test again. The precise folder name differs between boxed and Steam installations. Keep the original file because testing with a fresh logbook removes the existing history from view.
Windows permissions and blocked file writes
Blocked access to AppData, Documents or an add-on folder can leave FSX waiting during shutdown. Security protection, a synchronised Documents folder or an old add-on trying to write inside a protected installation directory may be responsible.
Run FSX as administrator once as a diagnostic. If that changes the behaviour, correct the affected folder permissions rather than relying automatically on permanent elevation. FSX and its companion utilities should also run at the same privilege level. Review security-protection records and allow only trusted simulator components instead of disabling protection wholesale.
Should I use the UIAutomationCore.dll fix?
Use a UIAutomationCore fix only when the lock-up follows use of FSX’s menu bar or Windows diagnostics identify that component. Our safe checks for UIAutomationCore menu faults cover that specific failure mode.
Do not treat a randomly sourced DLL as a universal exit-freeze fix. Most shutdown hangs are caused by an add-on module or external utility, and an unsuitable system file can introduce a separate crash.
What if FSX still will not close?
If a fresh profile and module-free stock flight still hang, verify the FSX: Steam Edition installation files after backing up modified core files. Verification repairs stock files but does not remove third-party add-ons or AppData configuration, which is why reinstalling or verifying alone often leaves the same fault in place.
Check Windows Reliability Monitor or the Application log for an application hang, faulting module or utility named at shutdown. If FSX displays a fatal error or drops to the desktop, use our broader FSX crash-isolation process instead. A clean installation that also fails outside add-on flights needs the Windows 10 and 11 compatibility checks for FSX, including permissions, DirectX components and boxed-versus-Steam differences.