https://devzone.nordicsemi.com/f/nordic-q-a/14929/read-dfu-verion-characteristic-failedUse SDK 10, SD version is 8.0. I add the dfu to the ANCS project. Then use the nRF Toolbox App to update the firmware, but it pop up &quot;Read DFU Verion characteristic failed&quot; as the picture.en-USTelligent Community 13Tue, 05 Jul 2016 09:12:41 GMThttps://devzone.nordicsemi.com/thread/56962?ContentTypeID=1Tue, 05 Jul 2016 09:12:41 GMT137ad170-7792-4731-bb38-c0d22fbe4515:4c35c63c-8c8e-4d56-bcdd-e88dc8adddccHung Bui<p>@hark&amp;mosi: Have you made sure you enabled IS_SRVC_CHANGED_CHARACT_PRESENT = 1 in both the application and the bootloader when testing ? You may need to delete bond (forget the device) turn off and on Bluetooth before testing. Do you have the same problem with the example in the SDK, and which SDK version you are testing with ?</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/56961?ContentTypeID=1Mon, 04 Jul 2016 15:54:10 GMT137ad170-7792-4731-bb38-c0d22fbe4515:0f219923-e61f-437f-b540-bc9068daf830mosi<p>I have the same problem. I&#39;m using nRF5_SDK_11.0.0_89a8197.</p> <p>The DFU app makes the app switch too bootloader mode but then I get this error message.</p><div style="clear:both;"></div>