https://devzone.nordicsemi.com/f/nordic-q-a/11326/nrfjprog-exe-error-invalid-serial-numberHi，I use nRFgo Studio to erase nRF51822, like this but it display: ERROR: Invalid serial number! I found the question how to use nrfjprog --snr??? ，I can get the same serial number when use &quot;nrfjprog.exe -i&quot;. But it aways &quot;Invalid serial numberen-USTelligent Community 13Wed, 20 Jan 2016 09:57:00 GMThttps://devzone.nordicsemi.com/thread/42598?ContentTypeID=1Wed, 20 Jan 2016 09:57:00 GMT137ad170-7792-4731-bb38-c0d22fbe4515:595a8558-5479-4028-8aef-1973c4257c49Stian R&#248;ed Hafskjold<p>I&#39;m glad it worked out for you. Please accept my answer if it is correct.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/42597?ContentTypeID=1Tue, 19 Jan 2016 15:16:26 GMT137ad170-7792-4731-bb38-c0d22fbe4515:52b40b93-fdd7-4a1e-a569-b1fd43c17b87Sin<p>Yes, it&#39;s a J-link. Everything is ok after I changed the J-link S/N with a 9 digit number. Thanks for your answer.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/42596?ContentTypeID=1Fri, 15 Jan 2016 15:00:52 GMT137ad170-7792-4731-bb38-c0d22fbe4515:acc5ff4d-8b2b-46b0-91fb-a48bc7f23ef7Stian R&#248;ed Hafskjold<p>Is this a J-link? I&#39;ve never seen a J-Link with a 10 digit serial number, but maybe I&#39;m wrong. Try to open J-Link configurator and see if every thing looks OK: <a href="https://www.segger.com/configurator.html">www.segger.com/configurator.html</a>. Maybe it&#39;s not a genuine one.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/42595?ContentTypeID=1Thu, 14 Jan 2016 21:01:13 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b807e374-7852-4ab5-9aed-6c16cd785bd6Wojtek<p>What programming tool are you using? Are you sure it is genuine one?</p><div style="clear:both;"></div>