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LICENSE: R003(0) Security key not found

Information in this knowledgebase article applies to:

  • any Keil product registered with a USB Dongle
  • MDK-ARM versions older than V4.60


During the compilation of my project I see an error message like:

Error: C9555E: Failed to check out a license.MISSING DEVICE (R003(0): SECURITY KEY NOT FOUND)
  • Is my connected USB Dongle broken and how can I get a replacement?
  • Or are there any other reasons known that end up with this error messages?


If your license is protected by a USB-Dongle:

If your license is not protected by a USB-Dongle:

  • If your product is the MDK-ARM Cortex-M only edition and you try to install a version older than V4.60 this error also rises. This product line was introduced with V4.60. The former MDK-ARM Standard- as well as the MDK-ARM Professional-licenses would work with MDK-versions before 4.60.



Last Reviewed: Tuesday, April 3, 2018

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