Fix FSX Acceleration installation errors on Windows 10 or 11 with the correct boxed-edition order, installer repairs and error-code fixes.
To fix FSX Acceleration installation errors on Windows 10 or 11, confirm you have boxed FSX, remove any incomplete Acceleration install, restart Windows, run FSX once as administrator, then run Acceleration’s Setup.exe locally as administrator. Do not install the boxed expansion over FSX: Steam Edition.
Is Acceleration for boxed FSX or Steam Edition?
The boxed Acceleration expansion is only for a boxed installation of Microsoft Flight Simulator X. FSX: Steam Edition already contains the Acceleration features and updated simulator files, so inserting an Acceleration DVD or applying boxed service packs to Steam Edition can damage the installation.
| FSX edition | What to install |
|---|---|
| Boxed FSX Standard or Deluxe | Install and activate base FSX, run it once, then install Acceleration. |
| FSX Gold Edition | Install the main FSX discs first, followed by the supplied Acceleration disc. |
| FSX: Steam Edition | Do not install boxed Acceleration, SP1 or SP2. |
If the edition is unclear, use our boxed-versus-Steam edition check before changing anything.
Clean installation steps for FSX Acceleration
The most reliable fix is to restore a working base FSX installation before running the Acceleration installer again.
- Remove the failed Acceleration installation. Open Windows’ installed-apps list and uninstall Acceleration if it appears there. Keep base FSX installed if it still launches correctly; do not start by deleting installer folders or registry entries manually.
- Restart Windows. Complete any pending Windows updates and restart again if requested. A pending restart can leave Windows Installer files locked and produce generic 1603 or 1722 failures.
- Launch base FSX as administrator. Right-click
fsx.exe, select Run as administrator, complete base-product activation, load a default flight and then close the simulator. This registers the installation path that Acceleration needs to find. - Use the correct update order. For FSX Gold or a separate Acceleration DVD, install Acceleration after the base simulator. Acceleration supplies the final updated simulator files, so standalone SP1 and SP2 packages are not required. Our explanation of the correct boxed FSX service-pack sequence covers the exceptions and edition differences.
- Copy the Acceleration DVD to the hard drive. Create a temporary folder such as
C:\FSX-ACC-SETUPand copy the entire disc into it. If Windows cannot copy a CAB file, the problem is the disc or optical drive rather than Windows Installer. - Run Setup with elevated rights. Right-click the copied
Setup.exeand select Run as administrator. Use the same Windows account that was used to install and launch base FSX. - Keep the existing FSX location. Acceleration must update the registered base installation. Do not move FSX to another folder manually between installing the base simulator and Acceleration.
- Check security notifications. If Windows Security or another security program records that it blocked Setup, allow the trusted DVD installer and retry. Avoid disabling protection unless a recorded block proves that it is interfering.
If a complete reinstall becomes necessary, installing boxed FSX in a writable folder such as C:\Games\FSX can reduce later add-on permission problems. An existing Program Files installation can still work; there is no need to reinstall solely because of its location.
Which FSX Acceleration error code are you seeing?
The error number usually identifies whether the failure comes from InstallShield, damaged media, Windows components or stale FSX installation data.
| Error | Likely cause | First action |
|---|---|---|
| 1607 or 1628 | InstallShield cannot initialise, access its working folders or start the required service. | Restart Windows, run Setup as administrator and then repair the InstallShield engine and permissions behind Error 1607. |
| 1603 | A generic fatal installer failure, often caused by permissions, locked files, a pending restart or remnants of an earlier attempt. | Restart, remove the incomplete Acceleration entry and retry from a local folder. |
| 1722 | An installer custom action failed, sometimes because FSX registration or licensing data is incomplete. | Confirm base FSX launches and is activated, then clear the installer and licensing state associated with Error 1722. |
| 1335 or a CAB-file message | The installer cannot read a compressed file from the disc. | Copy the DVD locally. If the same file will not copy, clean the disc or try another optical drive. |
| 1935 | Windows could not install or register an assembly or system component. | Repair Windows system files, restart and retry before changing FSX itself. |
Why does Acceleration Setup say FSX is not installed?
Acceleration usually fails to detect FSX when the base simulator has never been launched, was moved manually, was installed under another Windows account or has damaged registry information.
Run the original boxed FSX from its actual installation folder as administrator and close it normally. If that does not restore detection, repair or reinstall base FSX to create a valid registered path; copying an old FSX folder from another computer is not enough.
Should I use compatibility mode for the installer?
Administrator rights should be tried before compatibility mode on Windows 10 or 11. Permanent Windows XP compatibility settings can introduce different permission or activation problems, so use Windows’ compatibility troubleshooter only if Setup.exe will not start normally.
FSX is a 32-bit simulator, but it runs through the normal compatibility layer on 64-bit Windows. There is no separate 64-bit Acceleration installer to find.
What should I do after Acceleration installs?
Launch FSX as administrator once, enter the separate Acceleration product key if requested, load a default aircraft at a default airport and close the simulator normally. With FSX Gold, the base simulator and Acceleration commonly have separate keys, so using the base FSX key for the expansion will fail.
Test the clean simulator before restoring aircraft, scenery or utility add-ons. A crash after FSX reaches the menu is a runtime problem rather than an Acceleration installation error and should be diagnosed separately.