After installing the Android 5.1 update, Nexus 9 users might be getting the following error on their devices: “There’s an internal problem with your device. Contact your manufacturer for details.”

This is because Google added a check in Android 5.1 which compares /system/build.prop with the /vendor/build.prop, if they don’t match, the error is shown. To resolve this, you’ve a few values in /vendor/build.prop to match it with /system/build.prop file.

You could do this manually, but thanks to gladiac over at XDA for making a zip file that you could easily flash via custom recovery. It functions as follows:

I created an update-zip that corrects the values in /vendor/build.prop in a generic way (it should work no matter what rom you use). It mounts /system and /vendor, extracts the relevant information from /system/build.prop and creates a new /vendor/build.prop

[icon name=”download” class=”” unprefixed_class=””] Download build.prop fix for Nexus 9

How to Flash

  1. Install TWRP Recovery on your Nexus 9.
  2. Transfer the vendor-build-prop-fix-signed.zip file you downloaded above to your Nexus 9.
  3. Boot into Recovery Mode.
  4. Flash the zip file and DON’T wipe anything.
  5. Reboot your Nexus 9.

Done. The error will not show again now.