What it means
Cargo requires a connection to your 3D software in order to Install Plugins and to Import Assets.
Error 102 occurs when Cargo cannot connect to your 3D Software during Software Setup.
How to fix it
Check to make sure your 3D Software is shut down and go through Software Setup again. If your 3D software is running during Software Setup, the Cargo plugin will not be properly installed.
Only open your 3D software once the on-screen instructions direct you to activate the plugin within your 3D software.
You can find guides on how to do this for each 3D software here:
At the bottom of each guide, we include troubleshooting checkpoints to review that are specific to each 3D software.
Resolving Port Conflicts between Cargo and your DCC
If you are encountering handshake errors (like Error 102/103), shown an error that Cargo cannot detect your DCC or seeing a "Port already in use" message in your DCC, even when no other instances are running, you are likely experiencing a local port conflict.
This often happens because another background process or local server (such as the Autodesk Licensing Service, AdskLicen) is already listening on the default communication port that Cargo reserves for each DCC (Example: Cinema 4D uses port 49645.
You can permanently resolve this by manually assigning a new port for Cargo's DCC plugin.
How to Manually Change the DCC Port
The ports Cargo uses to communicate with 3D software plugins can be configured via a local configuration file called dccPortsConfig.json.
1. Locate your Configuration Folder
Depending on your operating system, navigate to your KitBash3D application data folder:
macOS:
~/Library/Application Support/kitbash3d/Windows:
C:\Users\YOUR_USERNAME\AppData\Roaming\kitbash3d\
2. Edit the Configuration File
Completely close both Cargo and the DCC.
Look for the file named
dccPortsConfig.json. If it doesn't exist, you can create a plain text file with this name.Open the file in a text editor (like TextEdit on Mac or Notepad on Windows).
By default, the file structures its port assignments like this:
{
"blender": 56565,
"cinema4d": 49645,
"houdini": 49637,
"3dsmax": 49636,
"maya": 49655,
"unity": 49656,
"unreal": 49635
}
5. Change the value of the DCC you're using from the listed port above to any other valid, open port number that isn't being used by your system (for example, 49650).
6. Save and close the file.
3. Restart and Verify
Relaunch Cargo, then open your DCC.
The Cargo Importer should now display Ready to Import, and your integrated tools (like Greyscalegorilla plugins) will be able to validate their licenses smoothly over the new port without background interference.
If you are still having issues after checking your plugin connection, contact us at info@kitbash3d.com and we’ll get you up and running in no time.