This article explains what a GATT error is and what you can do to resolve it.
If you are using the micro:bit with the mobile apps, you might come across a GATT error when you are trying to flash a program to the device.
The Generic Attribute Profile (GATT), defines the way that two Bluetooth devices transfer data back and forth, for example a micro:bit and a mobile phone.
When you try to flash a program, the mobile device or tablet will search to see if the micro:bit is advertising a service that let's the phone send a program to it. If it does not find the service, it will result in a GATT error.
Common errors include:
DFU SERVICE NOT FOUND
DFU CHARACTERISTICS NOT FOUND
and a full list can be found in the Android App repository on GitHub
If you find an error like this, please submit a support ticket or if you are comfortable using GitHub, please report it on
There is a great introduction to GATT on the Adafruit website.