Install and use SimConnect with MSFS 2020, including built-in setup, legacy runtimes, network configuration and connection fixes.
Microsoft Flight Simulator 2020 includes SimConnect, so most users do not install or enable it separately. Install your SimConnect-compatible companion app, start MSFS 2020, then launch the app and connect. Only legacy programs, networked clients or developers normally need extra runtime files, configuration files or the SDK.
SimConnect is an application programming interface, not a visible program or a mod for the Community folder. It lets flight planners, moving maps, hardware utilities and other Windows applications exchange data with the simulator. Our explanation of local and networked SimConnect connections covers what happens behind the scenes.
Do I need to download SimConnect for MSFS 2020?
A separate SimConnect download is unnecessary for an ordinary PC installation of Microsoft Flight Simulator 2020, including both Microsoft Store and Steam editions.
| Use case | What is required |
|---|---|
| Modern companion app on the MSFS PC | Install the app; MSFS supplies SimConnect |
| Older FSX-era application | Possibly the specific legacy runtime expected by that application |
| Application on another PC | Matching server and client configuration, plus firewall access |
| Writing your own application | The MSFS SDK and its SimConnect documentation |
| MSFS 2020 on Xbox | Windows SimConnect programs cannot be installed on the console |
How do I connect a SimConnect app to MSFS 2020?
- Check compatibility. Confirm that the companion program explicitly supports Microsoft Flight Simulator 2020. An application written only for FSX or Prepar3D may not work merely because a legacy runtime is installed.
- Install the companion application. Use its normal Windows installer. If that installer includes a required SimConnect redistributable, allow it to install the supplied component.
- Start MSFS 2020. Load into a flight before testing. Some clients can connect from the menus, but aircraft and flight data may not be available until the flight has loaded.
- Launch the companion app. Select MSFS or SimConnect if it offers a simulator choice, then press its connect control. Many programs detect the simulator automatically and show a connected status without a button.
- Test live data. Check that the app can see the loaded aircraft, position or simulator state. The launch order is usually flexible, although starting MSFS first avoids initial connection timeouts in clients that do not keep retrying.
Automatic launching is optional. Test the program manually first; if it works, it can then be added to the simulator's startup configuration. Our guide to editing exe.xml without breaking other launch entries explains that process.
When should I install a legacy SimConnect runtime?
Install a legacy runtime only when an older application specifically requires it or reports that its expected SimConnect assembly is missing.
Common symptoms include a SimConnect assembly error, a side-by-side configuration error or an older program that opens but cannot create its SimConnect client. Use the runtime bundled with the application or the appropriate Microsoft redistributable; our SimConnect installation and repair instructions cover the safe options.
Do not download a loose SimConnect.dll and copy it into the MSFS executable directory, Windows system folders or Community. That common shortcut can introduce the wrong library without installing the side-by-side assembly the program actually requests. Different legitimate legacy runtimes can coexist, so removing them at random may break another utility.
How do I use SimConnect over a network?
A remote client requires configuration on both computers; installing the application on the second PC is not enough.
- Connect both computers to the same trusted local network. Use the MSFS computer's private LAN address or a hostname that resolves reliably.
- Configure the SimConnect server. Place a valid
SimConnect.xmlon the simulator computer in the location specified by the application's instructions. - Configure the client. Put the matching
SimConnect.cfgwhere the remote application expects it. The protocol, address and port must agree with the server configuration. - Allow local firewall traffic. Permit the configured connection on private networks. Do not expose or forward the SimConnect port to the public internet.
- Restart and test. Restart MSFS and the client after changing either file, then load a flight and check the application's connection status.
Some utilities generate these files automatically, so use their supplied templates instead of combining examples from unrelated programs. Malformed XML, an obsolete IP address and mismatched ports are the failures we see most often.
Why will my SimConnect app not connect?
Most connection failures come from application compatibility, network configuration or a missing legacy dependency rather than SimConnect being disabled in MSFS.
- Wrong simulator profile: choose MSFS 2020 rather than FSX, Prepar3D or MSFS 2024 inside the companion application.
- No flight loaded: enter the cockpit before deciding that the connection has failed.
- Unsupported old client: installing a legacy runtime does not make every FSX utility compatible with MSFS 2020.
- Firewall or security software: check this especially for remote clients. A local client normally needs no manual port configuration.
- Broken network files: verify the port, protocol, server address and XML structure on both machines.
- Damaged or missing dependency: repair the companion app and install only the legacy runtime it documents.
- Stale process: close the companion app fully, restart MSFS and test again before reinstalling the simulator.
Developer Mode is not required for ordinary SimConnect utilities, and reinstalling the full SDK will not fix an incompatible consumer application.
Do I need the MSFS SDK to use SimConnect?
You need the SDK only to develop, compile or debug your own SimConnect client, not to run a finished companion application.
The SDK supplies documentation, definitions and samples; the simulator already supplies the runtime service used by normal clients. Developers can follow our guide to installing and starting the MSFS SDK rather than treating it as an end-user SimConnect repair package.