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CouldNotFindJprogDLL (0x2) despite installing nrf command line tools

Using the latest download and install of nrfconnect and nrf command line utils for a Win 64 machine, I am still finding that the PPK tools are unable to connect using the installed DLL.

Have installed 64 bit version of nRFProj 10.1.1 as suggested in similar ticket yet even after a reboot nRF Connect cannot find the DLL.

2019-06-25T09:44:47.319Z INFO Application data folder: C:\Users\awright\AppData\Roaming\nrfconnect\pc-nrfconnect-ppk
2019-06-25T09:44:47.324Z INFO App initialized
2019-06-25T09:44:47.595Z DEBUG App pc-nrfconnect-ppk v2.1.0 official
2019-06-25T09:44:47.595Z DEBUG App path: C:\Users\awright\.nrfconnect-apps\node_modules\pc-nrfconnect-ppk
2019-06-25T09:44:47.595Z DEBUG nRFConnect 2.7.0 is supported by the app (^2.4.0)
2019-06-25T09:44:47.595Z DEBUG nRFConnect path: C:\Users\awright\AppData\Local\Programs\nrfconnect\resources\app.asar
2019-06-25T09:44:47.595Z DEBUG HomeDir: C:\Users\awright
2019-06-25T09:44:47.595Z DEBUG TmpDir: C:\Users\awright\AppData\Local\Temp
2019-06-25T09:44:47.596Z ERROR Error while probing devices: Error occured when get serial numbers. Errorcode: CouldNotFindJprogDLL (0x2)

The PPK utility fails to validate if there is suitable firmware on my board, then goes on to pretend to read the current but shows no readings.

Path has been added to windows path so I can call the executable from anywhere

c:\>nrfjprog -v
nrfjprog version: 10.1.1
JLinkARM.dll version: 6.46d

Using nRFConnect 2.7.0


pc-nrfconnect-ppk v2.1.0

Is there a registry setting that needs modifying to let PPK know where to find the DLL, or is there an incompatibility with certain versions of the Nordic Tools or the J Link tools?

Many Thanks


  • Hi,

    I got this exact error on my system today. I solved it by Uninstalling nRF Connect, deleting the directories %LOCALAPPDATA%\Program\nrfconnect and %APPDATA%\nrfconnect, and then reinstalling nRF Connect. Could you try this?

    Best regards,

  • That's brilliant, thank-you all is now working as it should.

    Just for the record I had not got the folder %LOCALAPPDATA%\Program\nrfconnect, though I did find a couple of others with names that MIGHT have been relevant but probably weren't.  I figured it was worth deleting these anyway as part of the clean install.

    After uninstalling I deleted the 3 folders below, then reinstalled nRF Connect 2.7.0 and Power Profiler is now working perfectly.  Thank you so much for your speedy solution.

    • %LOCALAPPDATA%\Temp\nrfconnect-driver-install
    • %APPDATA%\nRF Connect
    • %APPDATA%\nrfconnect
  • Sorry, further to this it didn't quite work but showed me a work around.

    It seemed that the reason the DLL could be found when I reinstalled and launched is because I used the desktop shortcut to nRF Connect to launch the app and then selected Power Profiler.  This works every time.  However if I use the pull down arrow to create shortcut, and launch from the shortcut, then the DLL cannot be found.

    Working Shortcut

    Target "C:\Users\awright\AppData\Local\Programs\nrfconnect\nRF Connect.exe"

    Start In "C:\Users\awright\AppData\Local\Programs\nrfconnect"

    Failing Shortcut

    Target "C:\Users\awright\AppData\Local\Programs\nrfconnect\nRF Connect.exe" --args --open-official-app pc-nrfconnect-ppk --source official

    Start In ""


    Copy the start in folder location from the nRF Connect shortcut and paste it in the Power Profiler Shortcut.

    Now things are behaving as they should from both shortcuts.

  • Thank you for posting the solution. I have reported this internally to the developers!