Error: Unity Engine Input System Missing

What's Causing This Error

The error 'Unity Engine Input System Missing' typically occurs when the new input system package by Unity, known as InputSystem, is not correctly installed or configured in your project. There could be a few reasons behind this:

1. It's possible that you have recently upgraded your Unity version and the new version does not automatically come with the Input System package.
2. The package could be missing from the project due to some corruption, accidental deletion, or a fault during Unity installation.
3. Alternatively, if the Input System is installed but not enabled as the active input handling method, Unity might not recognize it and throw this error.

Solution - Here's How To Resolve It

To resolve the 'Unity Engine Input System Missing' error, follow these steps:

1. Install the Input System Package: Open your Unity project and go to Window -> Package Manager. In the Package Manager, make sure the dropdown at the top left is set to 'Packages: Unity Registry'. Scroll down to find the 'Input System' package, click on it, and then click 'Install'.

2. Activate the Input System: After installing the package, Unity will need to switch from the old input system to the new one. Typically, Unity should prompt you to do this automatically but if it doesn't, you can manually switch the systems: go to Edit -> Project Settings -> Player -> Other Settings and set 'Active Input Handling' to either 'Both' (if you want to use the new and old systems together) or 'Input System Package (New)'.

3. Restart Unity: After making changes to the input settings, restart Unity for the changes to take effect.

Should the problem persist even after following these steps, consider verifying your Unity installation or reinstalling Unity to ensure there are no issues with the installed files.