Fix the FSX requires XP SP2 error on Windows 10 or 11 by clearing incorrect compatibility settings and choosing the right update path.
The “Flight Simulator X requires XP SP2” message usually means FSX or its installer is running in an incorrect Windows compatibility mode—not that a modern PC needs Windows XP Service Pack 2. Clear compatibility mode for setup.exe or fsx.exe, run it again, and install XP SP2 only if the computer genuinely runs pre-SP2 Windows XP.
Why does FSX ask for XP SP2 on Windows 10 or 11?
FSX asks for XP SP2 when its old version check is being given the wrong Windows version. This commonly happens after the Compatibility troubleshooter or an old installation guide configures the executable for Windows XP Service Pack 1, Windows 98 or another obsolete release.
The original boxed edition did require Windows XP SP2 as a minimum, but later versions of Windows already exceed that requirement. Our breakdown of FSX system requirements and edition differences explains what the original specification means on a modern computer.
How do I remove the incorrect compatibility setting?
Remove compatibility mode from the executable producing the message rather than trying to install an XP service pack.
- Close FSX and its installer. If you use FSX: Steam Edition, close the simulator before changing its executable properties.
- Find the relevant executable. For a boxed installation, locate
setup.exeon Disc 1. If the error appears when starting FSX, locatefsx.exein the simulator’s installation folder. Steam users can open the installed-files location from the Steam library. - Open the Compatibility tab. Right-click the executable, select Properties, then open Compatibility.
- Clear compatibility mode. Untick Run this program in compatibility mode for. Do not select Windows XP SP2 as a workaround on Windows 10 or 11.
- Check the all-users setting. Select Change settings for all users, if shown, and clear compatibility mode there as well.
- Apply the change and try again. For an old boxed installer, running
setup.exeas administrator can help with file permissions, but administrator mode by itself does not correct the XP SP2 message.
If the DVD starts through autorun.exe, bypass it and launch setup.exe directly. Check autorun.exe for the same unwanted compatibility setting if the message appears before the main installer opens.
What if compatibility mode is already unticked?
A hidden per-user or all-users compatibility entry can remain even when the first Properties screen looks correct.
- Inspect the actual target. A desktop shortcut may point to a different copy of
fsx.exeorsetup.exe. Open the shortcut’s file location and check the executable itself. - Recheck all-users compatibility. Settings applied with another Windows account or administrator privileges can be stored separately.
- Reject automatic compatibility suggestions. If Windows offers to rerun the program with recommended settings, do not accept an XP or older-Windows mode.
- Check stored compatibility flags. Advanced users can inspect
HKEY_CURRENT_USER\Software\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\Layersand the equivalent path underHKEY_LOCAL_MACHINE. Back up the key first, then remove only a value whose name exactly matches the affectedsetup.exeorfsx.exepath. If there is no matching value, change nothing.
Do not download Windows XP SP2 for Windows 10 or 11, and do not alter Windows service-pack version values in the registry. Those approaches target the wrong problem and can create additional installation failures.
Which FSX edition and operating system do you have?
The correct action depends on whether this is boxed FSX, Steam Edition or a computer genuinely running Windows XP.
| Situation | Correct action |
|---|---|
| Boxed FSX on Windows 10 or 11 | Clear compatibility mode from setup.exe, then run the installer directly. |
| Installed boxed FSX | Clear compatibility mode from fsx.exe and the shortcut target. |
| FSX: Steam Edition | Clear compatibility mode from fsx.exe, then verify the installed files through Steam if the error remains. Do not install boxed-FSX service packs. |
| Windows XP before SP2 | The operating system genuinely fails the requirement. XP SP2 or SP3 satisfies it, although Windows XP is unsupported and should not be used online. |
Does this error mean I need FSX Service Pack 2?
No. Windows XP Service Pack 2 updates the operating system, while FSX Service Pack 2 updates the simulator. They are separate products despite the similar names.
Once boxed FSX installs successfully, apply its simulator updates in the proper order; our guide to the correct boxed-FSX service-pack sequence covers that process. FSX: Steam Edition already incorporates the later update baseline and must not receive the standalone boxed-edition service packs.
What if FSX still will not install or start?
Once every compatibility flag has been removed, restart Windows and try the exact executable again. Steam Edition users should verify the installation files; boxed-edition users should rerun Disc 1’s setup.exe rather than relying on autorun.
If an earlier attempt left a partial or damaged boxed installation, remove it before reinstalling. Follow our clean FSX removal procedure, then reinstall with compatibility mode disabled from the outset.