You cannot install FSX Acceleration on a different drive from boxed FSX. Learn the safe relocation method and avoid Steam Edition conflicts.
No. FSX Acceleration is an expansion for boxed Microsoft Flight Simulator X, not a separate simulator, so it must be installed inside the existing FSX folder on the same drive. If space is short, relocate the complete FSX installation correctly—usually by reinstalling it—before adding Acceleration.
Why must Acceleration be on the same drive as FSX?
The Acceleration installer reads the registered location of boxed FSX and adds or updates files throughout that installation. These include core simulator files as well as aircraft, gauges, effects, scenery and missions. A separate folder on another drive would not form a working standalone copy.
If the installer displays a destination, it must be the existing FSX root folder containing fsx.exe. Do not select an empty folder simply to place Acceleration elsewhere. Gold Edition follows the same rule because its Acceleration disc is an expansion for the base installation; our explanation of how FSX Gold packages the base simulator and Acceleration covers that relationship.
What should I do if the FSX drive is full?
The safest choice is to make room or relocate the whole boxed FSX installation before installing Acceleration.
| Situation | Correct choice |
|---|---|
| Boxed FSX is on the desired drive | Install Acceleration into the FSX folder detected by its installer. |
| Boxed FSX is on the wrong or full drive | Reinstall or properly migrate the complete FSX installation first. |
| FSX: Steam Edition is installed | Do not run the boxed Acceleration installer. |
Dragging the FSX folder to another drive is unreliable because Windows registry entries, uninstall records and add-on installers may continue pointing to the old path. Follow our safe method for moving FSX and its add-ons to another drive if preserving an established installation matters.
How should I reinstall boxed FSX on the new drive?
- Back up your custom content. Save add-on installers, liveries, scenery, saved flights and any configuration files you have deliberately changed.
- Remove any partial Acceleration installation. If Acceleration is already listed among installed applications, uninstall it before removing or relocating base FSX.
- Reinstall boxed FSX. Choose a folder on the destination drive, such as
D:\FSX, rather than copying the old directory manually. - Run base FSX once. Complete its activation, allow it to create its user files, then close the simulator.
- Install Acceleration. Let the installer use that same FSX folder, then launch FSX and complete the expansion’s activation.
- Restore add-ons selectively. Confirm the clean simulator works before reinstalling aircraft, scenery or utilities.
For permission problems, disc-installer failures and the correct setup sequence on newer versions of Windows, use our modern-PC installation guidance for FSX Acceleration.
Can FSX add-ons be stored on another drive?
Some add-ons can use another drive even though Acceleration cannot. Large mesh and photoreal scenery folders may be stored elsewhere and registered through the FSX Scenery Library, provided the add-on supports that arrangement.
Aircraft, gauges, effects and modules usually depend on specific locations inside the FSX directory. NTFS junctions or symbolic links can redirect folders, but we do not recommend using them to split Acceleration across drives: its installer, updates and uninstaller expect the registered FSX installation tree.
Does this apply to FSX: Steam Edition?
Boxed FSX Acceleration should not be installed over FSX: Steam Edition, on the same drive or any other drive. Steam Edition already incorporates the Acceleration content and functionality it requires, while the boxed expansion expects a registered boxed FSX installation.
If both editions are installed, keep them in separate folders and expect older add-on installers to identify the wrong copy occasionally. Our boxed FSX and Steam Edition comparison explains the installation and compatibility differences.