If you’re encountering Error E4 when trying to install a game onto an external SSD on macOS, follow these steps to resolve the issue:

Steps to Fix Error E4:

1. Delete the Problematic Installation Folder:

   • Open Terminal (you can find it via Spotlight search).
   • Run the following command to remove the installation folder:
      

     rm -rf "/path/to/your/external/drive/folder"

     Replace /path/to/your/external/drive/folder with the actual path of the installation directory (e.g., /Volumes/MyDrive/GoG/GameName).

2. Recreate the Installation Directory:

   • In Terminal, run the following command to recreate the folder:
      

     mkdir -p "/path/to/your/external/drive/folder"

   • Assign full permissions to the folder:

     sudo chmod -R 777 "/path/to/your/external/drive/folder"

     This grants read, write, and execute permissions, ensuring GOG Galaxy can access it.

3. Retry Installation:

   • Launch GOG Galaxy and attempt to install the game again to the same directory. It should now proceed without errors.

Why This Works

The error occurs because GOG Galaxy struggles to fix permissions on certain directories during installation. Manually resetting the folder resolves the conflict.

Let others know if this works for you! 😊