If you broke your installation of OMORI (meaning it doesn't work properly or at all), then you can fix your installation using Steam.

**This might override (delete) mod files, so make sure you back up files you want to keep.**

Save files should not be affected, but they might become unusable if they require a specific mod.

Here's how to fix your installation:
  - Open Steam
  - Right-click OMORI and choose //Properties//
  - On the tabs on the left, click //Local files//
  - Click //Verify integrity of game files...// This will make Steam check the files and cue an update to download fresh files from it's server if needed.