Download and install REX Atmos for MSFS on PC, choose the correct simulator version and Packages path, then solve activation and detection errors.
To install REX Atmos, download the Windows installer through the account or authorised retailer attached to your licence. Extract it, close Microsoft Flight Simulator, run setup, select the correct MSFS 2020 or 2024 Packages path if requested, activate and update Atmos, then launch it alongside the simulator before loading a flight.
Which REX Atmos version should I download?
Download only the REX Atmos build whose compatibility information explicitly names your edition of Microsoft Flight Simulator. Compatibility with MSFS 2020 does not automatically mean that an older installer can detect or connect to MSFS 2024.
| Simulator and platform | What to download | Key limitation |
|---|---|---|
| MSFS 2020 on PC | The Atmos build listed for MSFS 2020 | Check whether your licence includes later simulator support |
| MSFS 2024 on PC | A build explicitly marked as compatible with MSFS 2024 | An older 2020-only installer may not detect it |
| Xbox Series X|S or PlayStation 5 | No Windows installer | Desktop applications cannot be installed on a console; only a separately published in-sim Marketplace product could work there |
Our comparison of weather add-ons by MSFS version and platform can help confirm the compatibility limits before you buy or download anything. Do not assume that a PC licence transfers to an in-sim Marketplace edition.
How to download and install REX Atmos
- Confirm the simulator version. Check that the product page or order information names MSFS 2020, MSFS 2024, or both. Also confirm that you are using Windows rather than a console.
- Open the account used for the purchase. Download Atmos from the REX account or authorised retailer associated with the order. If the order supplies a REX product manager rather than a direct installer, install that manager first, sign in or redeem the supplied serial, and let it retrieve Atmos.
- Extract the complete archive. If the download is a ZIP or similar archive, extract every file to a normal temporary folder before running setup. Do not start the installer from inside the archive. Our guide to extracting simulator downloads without nested-folder errors covers this common failure point.
- Close MSFS and other weather tools. This prevents locked files and stops another weather application from interfering with the first connection test.
- Run the supplied setup program. Use the normal installation location offered for the Atmos application. Administrator rights are usually needed only when Windows blocks the installer from writing to a protected location.
- Select the correct simulator path if asked. When setup requests the Packages folder, choose the folder containing
CommunityandOfficial. If it specifically requests the Community folder, selectCommunityitself. Never choose the protectedWindowsAppsdirectory merely because the Microsoft Store installed the simulator there. - Activate and update Atmos. Enter the licence details exactly as supplied by the seller, then allow the application or product manager to install any available update before connecting to MSFS.
- Start MSFS and Atmos. Wait for Atmos to report that it has found the intended simulator before applying a weather or atmosphere profile. Use the in-sim weather mode required by that Atmos mode, and keep every other external weather injector disabled.
Where should REX Atmos be installed?
The Atmos desktop application belongs in the normal Windows application location selected by its installer, not as a folder copied wholesale into Community. If Atmos needs an MSFS package, its installer or product manager should place that component in the correct location.
The simulator executable folder and the Packages folder are not the same thing. Microsoft Store, Steam and custom installations can all keep Packages elsewhere, so use our instructions for finding the active MSFS Packages and Community folders if automatic detection selects an old or empty location.
Why does the REX Atmos installer not detect MSFS?
Detection usually fails because the installer is outdated, the wrong simulator edition was selected, or MSFS uses a custom Packages path. Correct the path or obtain the compatible Atmos build rather than repeatedly reinstalling the same files.
- MSFS 2024 is missing from the installer: update the REX product manager or download a build whose compatibility list explicitly includes MSFS 2024.
- The Community folder is empty: verify that you selected the active Packages location used by the simulator, not an abandoned folder left by a previous installation.
- Activation is rejected: use the account and serial associated with that retailer's order. Remove accidental spaces when pasting the key.
- Setup files disappear: verify that the download came from the legitimate purchase account, then inspect Windows Security's quarantine before downloading it again.
- Atmos connects but has no effect: disable other weather injectors, confirm the required in-sim weather mode and wait until Atmos reports a simulator connection.
If installation completes but weather still does not appear, follow our focused checks for REX Atmos connection, weather and configuration problems. Reinstalling should come after checking the selected simulator, Packages path, weather mode and competing injectors.
Does REX Atmos need FSUIPC7 or a manual Community install?
Do not add FSUIPC7 or manually move Atmos files into Community unless the documentation supplied with your particular build explicitly requires it. Atmos should be installed through its own setup or product manager; adding unrelated connection software does not repair an incorrect simulator path or an unsupported Atmos build.