Hi-Fi Rush is a rocking game when everything is in sync. Unfortunately, errors tend to throw all of it into disarray. Here's how to correct the UE4 fatal error bug in Hi-Fi Rush.
Related: How many chapters are there in Hi-Fi Rush?
Hi-Fi Rush's UE4-Hibiki Game Error: How to Fix It
If you are getting a message in Hi-Fi Rush saying there was a UE4 (Unreal Engine 4, the game's engine) error, it's probably because you must remove the game and reboot it. The second reason is that you're trying to run the game while it's fully installed. If you do this, close the game and let it finish installing.
Check to make sure your graphics card is up to date. In the Search box on your Taskbar, go to Device Manager. Find your graphics card, right-click it, and select Search Automatically for Updated Driver Software.
If your game says it is fully installed and there is no driver update, we recommend restarting your system and checking for any updates. If neither of these works, you may have some corrupted files installed. You can either completely uninstall and reinstall them.
This Unreal Engine 4 flaw is quite common on the Steam version of Hi-Fi Rush, so you may need to wait for a patch to fix it.