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An image or resource file is invalid

Android / Gradle · last reviewed 2026-11-10

The error looks like this

[stderr] ERROR:/home/expo/workingdir/build/android/app/build/generated/res/react/release/drawable-mdpi/assets_images_library.png: AAPT: error: file failed to compile.

Why it happens

Android could not process the file named in the message — usually a JPEG or WebP saved with a .png extension, or a corrupt image.

How to fix it

  1. Open the file named in the error and re-export it as a real PNG.
  2. Check its real type: file path/to/image.png
  3. File names must be lowercase letters, digits and underscores only.

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