.NET for Android error/warning APT0000

Example messages

error APT0000: res\drawable\image (1).png: Invalid file name: must contain only [a-z0-9_.]
error APT0000: Resource entry resource_name is already defined.
error APT0000: No resource found that matches the given name (at 'resource_name' with value '@string/foo').
error APT0000: invalid resource directory name: obj\Debug\dir with spaces "dir with spaces".
warning APT0000: warning: string 'resource_name' has no default translation.

Issue

This message indicates that aapt (Android Asset Packaging Tool) reported an error or warning. aapt is part of the Android SDK and is used internally by .NET for Android to process and compile resources into binary assets.

Errors reported by aapt are outside of .NET for Android's control, so a general error code of APT0000 is used reporting the exact message coming from aapt.

Solution

To learn more about aapt and Android resources, see the Android documentation.