Hello,
What does EU-FA-503 mean?
This error typically indicates connectivity issues between the Epic Games Launcher and the servers. It might be due to:
- Internet instability
- A firewall/antivirus is blocking the connection
- Launcher configuration or cache corruption
- Temporary server-side issues
Recommended Troubleshooting Steps
1. Restart and Check the Internet
- Fully close the Epic Games Launcher (via Task Manager).
- Restart the computer.
- Ensure they have a stable internet connection.
2. Run as Administrator
- Right-click the Epic Games Launcher icon.
- Select “Run as administrator.”
This often resolves permission-related installation issues.
3. Clear the Launcher Cache
- Close the launcher.
Navigate to:
C:\Users[YourUsername]\AppData\Local\EpicGamesLauncher\Saved
- Delete the folder named “webcache.”
- Reopen the launcher.
4. Check for Launcher Updates
- Once reopened, ensure the Epic Games Launcher is fully up to date.
5. Use the Direct Installer
Try launching the Application in this case, RealityCapture, directly from the App folder here:
C:\Program Files\Capturing Reality\RealityCapture
If you are still experiencing an Issue, please report a bug [Here] (RealityScan Support - RealityScan) and provide latest log found here 
C:\Users\username\AppData\Local\EpicGamesLauncher\Saved\Logs
Thank you