How do I run or fix FS2004 on Windows 10 or 11?

Microsoft Flight Simulator 2004 can run on Windows 10 and Windows 11. Install it outside Program Files, apply the official 9.1 update and test default content first. If the boxed edition installs but will not launch, its blocked SafeDisc disc check—not modern hardware—is usually responsible.

Does Flight Simulator 2004 run on Windows 10 and Windows 11?

Yes—FS2004's 32-bit simulator engine works under Windows 10 and Windows 11, although both operating systems were released long after official support ended.

The main trouble spots are unsupported disc authentication, User Account Control, file redirection and add-ons written for an XP-era installation. Compatibility mode can help with a specific display or permission fault, but it cannot restore an obsolete disc-check driver.

If the simulator is not installed yet, follow our detailed FS2004 disc-installation sequence. Its folder, update and clean-install guidance applies to Windows 10 as well as Windows 11.

How do I install and run FS2004 on a modern PC?

The dependable method is a clean installation in a writable folder, updated and tested before any third-party content is added.

1. Run setup from the original media. If the old autorun menu does nothing, browse the disc in File Explorer and start its setup executable directly. Use administrator rights for the installer only if Windows reports a permission or write error, and keep the same destination while changing discs.
2. Install outside protected folders. Choose a simple path such as C:\FS2004 or C:\Games\FS2004, not Program Files. This prevents many UAC, VirtualStore and old add-on installer problems.
3. Leave the installation unmodified. Do not copy old Aircraft, Gauges, Modules or scenery folders into it yet. That can return the original fault before the base simulator has been proved.
4. Apply the final official update. Install the official FS2004 v9.1 update package before adding aircraft or utilities. The updater must be pointed at the correct, unmodified FS2004 folder. It fixes simulator faults and is expected by many add-ons, but it does not remove the disc check.
5. Make the first flight with default content. Use a default aircraft and airport. The standard four-CD edition normally asks for Disc 4 when starting; if it fails before the menu, investigate disc authentication rather than graphics settings.
6. Test windowed operation. Once FS2004 opens, press Alt+Enter to compare windowed and full-screen modes. Set the desired resolution only after the basic installation is stable.
7. Reset the configuration if startup fails. Rename %APPDATA%\Microsoft\FS9\fs9.cfg to fs9.cfg.old. FS2004 will generate a clean file when it next starts successfully.
8. Add extras gradually. Install one aircraft, scenery package, gauge set or utility at a time, launching FS2004 after every change.

Which FS2004 failure do you have?

The point at which FS2004 fails usually identifies the right repair faster than reinstalling or enabling every compatibility option.

Why does boxed FS2004 install but not launch?

The original boxed release can install normally and then fail because Windows 10 and Windows 11 do not support the legacy SafeDisc mechanism used for disc authentication.

The failure may misleadingly request administrator access or valid media. In other cases, fs9.exe appears briefly in Task Manager and disappears without an error. Administrator mode, Windows XP compatibility and graphics-driver changes cannot restore the blocked secdrv.sys driver.

For a lawfully owned installation already updated to v9.1, use a version-matched v9.1 no-CD replacement where local law permits. This is an unofficial modified executable, not part of Microsoft's 9.1 update.

• Back up the original fs9.exe before replacing it.
• Match the replacement to the installed version. Do not combine an original-release executable with a v9.1 installation.
• Check Windows Security's protection history if a replacement is quarantined; do not disable antivirus protection globally.
• Do not download or try to re-enable an abandoned secdrv.sys driver from an unknown source.

A dedicated legacy Windows installation kept offline is another option. A virtual machine may work, but limited 3D acceleration and unreliable joystick support often make it a poor choice for FS2004.

Does FS2004 need compatibility mode?

FS2004 often runs with every compatibility option disabled, so use a normal launch first and change only one setting at a time.

Our explanation of when compatibility mode helps older simulators separates faults it can address from disc protection, missing components and broken add-ons. For display-specific trouble, use the FS2004 full-screen troubleshooting steps rather than changing unrelated options.

Before applying compatibility settings, reset fs9.cfg, remove graphics-driver anti-aliasing and frame-rate overrides, and disable recording overlays or monitoring software that hooks into 3D applications. If only full-screen mode fails, test the full-screen optimisation option by itself.

It still does not open after installation—what next?

Diagnose the exact launch stage with no add-ons present, making only one change between attempts.

Nothing happens when fs9.exe starts

When no window or splash screen appears, the boxed edition's disc check is the leading suspect. End any stranded fs9.exe process in Task Manager before trying again, then check Windows Security's protection history for a quarantined executable.

If no fs9.cfg has ever been created, FS2004 probably has not progressed far enough for its configuration or display settings to be responsible.

The splash screen appears and then closes

A splash-screen exit usually points to the configuration, startup flight or a DLL-style add-on loaded during startup.

Enter %APPDATA%\Microsoft\FS9 in File Explorer's address bar and rename fs9.cfg; keep the old file until the replacement has been tested. If the crash remains, inspect Windows Reliability Monitor. A named third-party .dll or .gau file is a useful lead, while fs9.exe alone does not reveal the underlying cause.

Why do settings or scenery changes not stick?

Settings that appear to save and then vanish usually mean Windows is redirecting files from a protected installation folder.

Look under %LOCALAPPDATA%\VirtualStore for another copy of files from the FS2004 path. A mistake we see constantly is editing the visible file under Program Files while the simulator uses a redirected copy elsewhere. Reinstalling into C:\FS2004 is cleaner than maintaining both locations.

If FS2004 cannot save flights or user files, check whether controlled-folder protection blocked the write. Allow only a verified executable instead of switching that protection off globally.

Why did FS2004 stop working after an add-on?

If the default simulator works and the fault starts after adding content, treat the newest aircraft, panel, gauge, module or scenery package as the cause until it is ruled out.

Add-ons must go into the actual FS2004 installation tree, not an old path suggested by their installer. Aircraft normally belong under Aircraft; scenery is commonly placed under Addon Scenery and then activated inside FS2004. Confirm every destination manually.

Some XP-era installers fail on 64-bit Windows even though the aircraft or scenery itself remains usable. Follow documented manual-installation instructions when supplied, and do not guess where shared gauges or modules belong. Never merge an entire old Gauges or Modules folder into a clean installation.

If FS2004 opens but later crashes, test a default aircraft at a default airport in windowed mode. Restore old gauges, modules, AI traffic and dense scenery in small groups. FS2004 is a 32-bit application, so adding system RAM does not remove its limited process address space; persistent in-flight faults need the separate FS2004 crash-isolation process.

Once the default simulator is stable, our curated FS2004 aircraft, scenery and utility library provides add-ons that can be introduced in controlled stages.