Unable to pair to ble_app_hrs using nRF Connect v2.6.1

[Fredrik]

Hi all,

I'm trying to learn more about the pairing and bonding procedures in the SDK. I connected one nRF52480 DK to my computer (running Ubuntu 16.04) and let nRF Connect v2.6.1 flash it with "the latest connectivity firmware". The other nRF52840 DK was flashed with the Heart Rate Application from SDK v14.2. I am able to scan, connect and subscribe to characteristics through nRF Connect, but when I attempt to pair the two devices I get the following error in nRF Connect: "Failed to reply security parameters. (NRF_ERROR_INTERNAL)". The log says the following:

It does not matter which checkboxes I check in the popup before clicking "pair". I enabled logging in the Heart Rate Sensor application, but I cannot see any errors there. I tried two different DKs in nRF Connect.

nRF Connect for Android seems to have no problems bonding to the Heart Rate Sensor application.

Any help is appreciated.

Best,

Fredrik

[Fredrik]

Digging some more I found the solution in Jørgen's answer in this question. Following workaround 2 here worked for me (replace "J-Link Commander" with "JLinkExe" and you should be good).