ADD SIMCONNECT TO FS24

SimConnect setup for JBCAS

Use this guide if you received a JBCAS package (SimHost, SimConnector, ATC Console, or the full server kit) and SimConnect is not working, or if you want to understand what “installing SimConnect” actually means on a new PC.

Microsoft Flight Simulator edition: These steps work the same whether you bought MSFS from the Microsoft Store or Steam. The SDK installer is downloaded from inside the simulator, not from the store app.

 The short version

1. You do not install a separate “SimConnect program.” SimConnect is built into Microsoft Flight Simulator. It is only active while the sim is running with a flight loaded.

2. If your JBCAS folder already contains the two DLL files (see below), you usually do not need to install the SDK. Copy the package, start MSFS, then run `JBCAS.SimHost.exe` or `SimConnector.exe`.

3. If those DLL files are missing or you get SimConnect errors, install the MSFS 2024 SDK once, copy the official DLL pair into your JBCAS app folder, and try again.

 What JBCAS needs (two files)

JBCAS apps that talk to the simulator need both of these files in the same folder as the `.exe` you run:

| File | Purpose |

|------|---------|

| `Microsoft.FlightSimulator.SimConnect.dll` | .NET wrapper used by JBCAS |

| `SimConnect.dll` | Native 64-bit SimConnect client (must sit next to the exe) |

Typical locations in your package:

SimHost\

  JBCAS.SimHost.exe

  SimConnect.dll

  Microsoft.FlightSimulator.SimConnect.dll

SimConnector\

  SimConnector.exe

  SimConnect.dll

  Microsoft.FlightSimulator.SimConnect.dll

# Quick check (Windows)

1. Open the folder that contains `JBCAS.SimHost.exe` or `SimConnector.exe`.

2. Confirm both DLL names above are present.

3. If both are there, skip to “Daily use” below.

> Important: Do not copy `SimConnect.dll` from old simulators (FSX, Prepar3D, etc.). The MSFS 2024 managed wrapper requires the MSFS 2024 native DLL. A wrong pair causes immediate connect failures or crashes.

 Option A — Normal users (recommended)

If you received a complete JBCAS package from your administrator, the DLLs should already be bundled. You only need:

1. Microsoft Flight Simulator 2024 installed and updated.

2. .NET 8 Desktop Runtime (Windows x64) — one-time install from Microsoft if the app says the runtime is missing:  

   https://dotnet.microsoft.com/download/dotnet/8.0  

   Choose “.NET Desktop Runtime 8.x” for Windows x64.

3. Start MSFS 2024, load into a flight (not just the main menu).

4. Run JBCAS.SimHost or SimConnector and connect.

No SDK install required.

 Option B — Install the MSFS 2024 SDK (when DLLs are missing)

Use this when:

- One or both SimConnect DLLs are missing from your JBCAS folder.

- The app reports SimConnect failed to initialize / DLL not found.

- You are setting up a new PC and the package did not include the DLLs.

You only need to do this once per computer. After you copy the DLLs into your JBCAS folder, you do not need to run the SDK installer again for day-to-day flying.

# Step 1 — Turn on Developer Mode in the sim

1. Launch Microsoft Flight Simulator 2024.

2. Open Options (gear icon) → General → Developers (or Developer).

3. Turn Developer Mode On.

4. A developer menu bar appears at the top of the screen.

# Step 2 — Download the SDK installer from the sim

1. In the developer menu bar, click Help.

2. Choose SDK Installer or SDK Installer (Core) (wording may vary slightly by sim version).

3. When prompted, pick a folder to save the download (e.g. `Downloads`).

4. Wait for the download to finish. You will get a .zip file, often named like:  

   `MSFS2024_SDK_Core_Installer_1.x.x.zip`

# Step 3 — Install the SDK on Windows

1. Close Microsoft Flight Simulator (recommended before running the installer).

2. Open the downloaded .zip and extract it.

3. Run the .msi installer inside (e.g. `MSFS2024_SDK_Core_Installer_1.x.x.msi`).

4. Accept the license and use the default install location unless you have a reason to change it.  

   Default is usually: `C:\MSFS 2024 SDK\`

5. Finish the installer. You do not need Visual Studio or 3ds Max for JBCAS — skip or cancel those optional components if asked.

# Step 4 — Find the official SimConnect DLL pair

After the SDK installs, look under the SimConnect SDK folder. Common layouts:

MSFS 2024 (most common):

C:\MSFS 2024 SDK\SimConnect SDK\lib\Managed\Microsoft.FlightSimulator.SimConnect.dll

C:\MSFS 2024 SDK\SimConnect SDK\lib\SimConnect.dll

Sometimes the native DLL is here instead:

C:\MSFS 2024 SDK\SimConnect SDK\bin\SimConnect.dll

Older / alternate SDK layouts (if you installed an older kit or a different path):

C:\MSFS SDK\SimConnect SDK\...

Steam-installed sim (only if the SDK was deployed next to the game — less common than `C:\MSFS 2024 SDK\`):

C:\Program Files (x86)\Steam\steamapps\common\MicrosoftFlightSimulator\SDK\SimConnect SDK\...

Use File Explorer search on `C:\` for `Microsoft.FlightSimulator.SimConnect.dll` if you are unsure. When you find it, look in the same folder or in a sibling `lib` or `bin` folder for `SimConnect.dll`.

# Step 5 — Copy the DLLs into your JBCAS app folder

Copy both files into the folder that contains the JBCAS exe you run:

| Copy from (SDK) | Copy to (your package) |

|-----------------|------------------------|

| `Microsoft.FlightSimulator.SimConnect.dll` | Same folder as `JBCAS.SimHost.exe` and/or `SimConnector.exe` |

| `SimConnect.dll` (native, x64) | Same folders |

If you use both SimHost and SimConnector, each exe folder needs its own copy of the pair.

# Step 6 — Verify file size (avoid wrong DLL)

The correct MSFS native `SimConnect.dll` is large (hundreds of KB or more). If your `SimConnect.dll` is only about 58–60 KB, it is probably from FSX/Prepar3D and will not work. Delete it and copy the one from the MSFS 2024 SDK only.

---

 Daily use (every flight)

SimConnect is not a Windows service you start separately.

1. Start Microsoft Flight Simulator 2024.

2. Load a flight (Free Flight, career, etc.). Main menu only is often not enough.

3. Start your JBCAS app (SimHost, SimConnector, or the full stack).

4. Confirm the app shows connected to the sim.

Order matters: MSFS first (with a loaded flight), then JBCAS. If JBCAS starts before the sim, close JBCAS, load the flight, and start JBCAS again.

 Troubleshooting

| Symptom | What to try |

|---------|-------------|

| “SimConnect.dll not found” or DLL load error | Confirm both DLLs are in the same folder as the `.exe`. Re-copy from the SDK (Option B). |

| Connect fails immediately | MSFS not running, or no flight loaded. Start sim first. |

| Stuck on “Connecting to Sim” | Load into the cockpit/world; wait 30–60 seconds after the flight is fully loaded. |

| Worked on one PC, not another | Compare DLL presence and .NET 8 Desktop Runtime on the new PC. Re-copy the MSFS 2024 DLL pair — do not copy from FSX/P3D. |

| “You must install .NET” | Install .NET 8 Desktop Runtime x64 (see Option A). |

| SimConnect worked before an MSFS update | Reinstall or repair the SDK from Help → SDK Installer in the sim, then re-copy the DLL pair into your JBCAS folder. |

| Steam vs Microsoft Store | SDK install is the same (in-sim Help → SDK Installer). Game install path differs; SDK default path is still usually `C:\MSFS 2024 SDK\`. |

# Firewall and antivirus

JBCAS talks to the sim on the same PC. You should not need to open inbound firewall ports for local SimConnect. If security software quarantines `SimConnect.dll`, restore it from the official SDK copy.

What you do not need

- A separate SimConnect installer from Microsoft’s website (there isn’t one for end users like the old FSX days).

- Developer Mode turned on for every flight (only needed to download the SDK).

- Visual Studio, unless you are building JBCAS from source.

- Installing SimConnect on a PC that does not run Microsoft Flight Simulator — SimConnect only connects to a running sim on that same machine.

 Official Microsoft documentation

- [MSFS 2024 SDK overview](https://docs.flightsimulator.com/msfs2024/html/1_Introduction/SDK_Overview.htm)

- [SimConnect SDK](https://docs.flightsimulator.com/msfs2024/html/6_Programming_APIs/SimConnect/SimConnect_SDK.htm)

- [SimConnect managed code (.NET)](https://docs.flightsimulator.com/msfs2024/html/6_Programming_APIs/SimConnect/Programming_SimConnect_Clients_Using_Managed_Code.htm)

 Support

For JBCAS package updates, server URLs, and community access, contact your JBCAS administrator.  

For SimConnect file recovery on a new PC, follow Option B above or request a fresh package that already includes the DLL pair.