Decide whether to move from FSX to Prepar3D, then follow our safe checklist for migrating aircraft, scenery, controls, utilities and flight plans.
We recommend moving from FSX or FSX: Steam Edition to a 64-bit Prepar3D release if you need more memory headroom and your essential add-ons support that exact version. Do not copy the whole FSX installation; install P3D cleanly, then migrate compatible aircraft, scenery, utilities, controls and flight plans one category at a time.
Should you switch from FSX to Prepar3D?
Switch if FSX’s 32-bit limits are disrupting the flights you actually make and every indispensable add-on has a supported replacement.
Prepar3D v4 and later are 64-bit, so they avoid the restrictive address-space ceiling behind many FSX out-of-memory errors. That does not guarantee higher frame rates: processor speed, graphics hardware, scenery complexity and simulator settings still determine performance.
Prepar3D is licensed for specified learning, training, simulation and professional uses rather than as a conventional entertainment game. Confirm that the licence for your intended edition covers how you plan to use it.
| Decision point | Stay with FSX | Move to Prepar3D |
|---|---|---|
| Add-on library | Your essential aircraft or utilities are FSX-only. | Your must-have products explicitly support the chosen P3D major version. |
| Main problem | FSX is stable and meets your needs. | Complex aircraft and scenery regularly cause memory exhaustion. |
| Hardware | You use an older system on which FSX already performs acceptably. | Your computer meets the requirements of the specific P3D release and its graphics features. |
| Time and cost | You do not want to rebuild or replace a working installation. | You accept a clean reinstall and possible new add-on licences. |
Do not assume the newest P3D release is automatically the right one. Choose the major version supported by your aircraft and utilities. Our practical FSX-versus-Prepar3D comparison explains the broader differences in architecture, graphics, hardware demands and add-on support.
What do you need to migrate from FSX?
Migrate only your user-created files and add-ons confirmed as compatible; the FSX programme files and configuration files should remain behind.
| Category | Migration action | Main compatibility risk |
|---|---|---|
| FSX core content | Do not migrate it or merge the simulator folders. | Default gauges, DLLs, textures and configuration files can damage or destabilise P3D. |
| Aircraft and repaints | Use a P3D-specific installer where available. Copy repaints only after installing a compatible base aircraft. | Old model formats, 32-bit gauge DLLs, modules and protected installers may fail. For P3D v5, follow our aircraft-by-aircraft migration checks. |
| Scenery and mesh | Reinstall each package and recreate its priority using the supported P3D method. | Simple BGL scenery often works, but object libraries, elevation corrections, autogen definitions and installer modules may not. |
| Utilities and modules | Install a build matching the exact P3D release and its 64-bit architecture. | FSX DLLs cannot simply be copied into 64-bit P3D. This includes checking which FSUIPC generation fits the simulator. |
| Controls and camera settings | Record the old assignments, then recreate them in P3D or import only a supported profile. | Controller identifiers and available commands differ; replacing P3D’s configuration with an FSX file creates conflicts. |
| Flight plans and saved flights | Copy ordinary .pln flight plans and verify them in P3D. | Saved flights, weather states and aircraft-specific panel states are not reliably portable. |
| AI, weather and navdata | Reinstall each system using a version that targets your chosen P3D release. | Old traffic models, weather hooks, database paths and global texture replacements can be version-specific. |
How do you migrate from FSX to Prepar3D safely?
- Choose the target P3D version. Base the decision on licence terms, hardware and support for your must-have aircraft, scenery and utilities—not merely the highest version number.
- Inventory the FSX installation. Separate essential add-ons from those you no longer use. Record each product’s version, dependencies and installation source.
- Back up user-created material. Preserve flight plans, repaints, custom scenery, controller references and licence details. Treat the backup as a reference, not a folder to restore over P3D.
- Install and test stock Prepar3D. Run a default aircraft at a default airport before adding anything. Resolve graphics, sound and controller problems at this stage.
- Rebuild the controls. Assign each axis in one place only. If an external utility manages an axis, remove the duplicate P3D assignment.
- Install compatible add-ons individually. Add shared object libraries before scenery that depends on them, then install aircraft and utilities one at a time. Our guide to setting up removable P3D add-on packages explains the preferred package method and legacy alternatives.
- Test after every installation. Load the aircraft, operate its gauges, inspect its sounds and effects, visit the scenery, then close and restart P3D. This identifies the last change immediately if something fails.
- Keep FSX installed during the transition. Remove it only after representative flights with your normal aircraft, airports, weather and controls work correctly in P3D.
Why do migrated FSX add-ons fail in Prepar3D?
Most failures come from copying an add-on that looks self-contained but depends on an incompatible gauge, DLL, object library or configuration entry elsewhere in FSX.
- Crash while selecting an aircraft: remove the last aircraft and check for an old gauge DLL or module that cannot run in 64-bit P3D.
- Black or transparent instrument panel: install the correct P3D gauge package rather than replacing textures at random.
- Missing or duplicated scenery: confirm that the package is enabled, its path is valid, required object libraries are present and its priority is correct.
- Erratic controls: remove duplicate axis assignments between P3D and any controller utility.
- Installer detects only FSX: do not spoof registry entries or point it at the P3D root folder. Use a P3D-specific installer or migrate manually only when the add-on’s documentation confirms compatibility.
Can FSX and Prepar3D remain installed together?
Yes. FSX, FSX: Steam Edition and Prepar3D can coexist when each has separate programme, configuration and add-on folders.
Avoid linking entire SimObjects, Gauges or scenery directories between them. One simulator’s update or incompatible file can then break both. Keeping FSX available is especially sensible when one or two FSX-only aircraft still define the flying you do.
Our practical rule is simple: keep FSX if its add-on library matters more than P3D’s memory headroom. Move—or run both—when compatible P3D versions exist and FSX’s 32-bit limitations have become the main obstacle.