This error usually comes up when either the Livelink was not installed in the correct location or the Livelink could not initialise the socket properly. It also comes up when you attempt to export from Bridge but Unreal Engine is not running.
To solve this problem, first, make sure that both Bridge and Unreal Engine are running. If the issue still lingers, check if there is a green M button inside Unreal Engine.
If you don't see the button in Unreal Engine, it means the livelink was either not installed properly or was installed in the incorrect location.
To fix this, first, close Unreal Engine.
Then select one of your Downloaded assets in Bridge and check if the Installation Folder was set to point to the correct location. It should be set to where your engine's plugins are installed, like this for instance: C:\Program Files\Epic Games\UE_4.22\Engine\Plugins. The path should basically be where your engine's plugins are installed.
If all else fails, i.e. your Installation Folder is correct but you still don't see the green Megascans button in UE4, then remove and re-install the livelink as follows:
- Close both Bridge and UE4.
- Goto C:\Users\[Username Goes Here]\AppData\Roaming\Bridge and delete Settings (take a backup before deleting).
- Goto C:\Program Files\Epic Games\UE_4.XX\Engine\Plugins and delete UnrealEnginePython folder. (this directory could be different depending on where UE4 is installed on your machine)
- Goto the folder specified in the Local Library Path in Bridge > Edit > Settings, on your machine and delete the support folder inside it.
- Launch Bridge using “Run as Administrator” option (keep UE4 closed).
- Goto Export Settings and download Unreal Plugin.
- Once downloaded, select the correct version and specify path to Engine directory inside UE4.
- You should see a notification that says installing UE4 plugin.
- Please wait till you see another notification that says installation complete.
- Open UE4 and LiveLink should be working.