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ULINK: Debug issue - "USB Communication Failure" on Windows 8.x and 10

Information in this knowledgebase article applies to:

  • MDK-ARM V5.16a and earlier
  • ULINK2, ULINKPro, ULINKPro-D debug adapter
  • Windows 8.x and Windows 10


I'm working on a MDK-ARM v5.x.x project within Windows 8.x. The erase/program/verify procedures on the target device via a ULINK2 or ULINKPro debug adapter work fine. But the debug session does not always start properly. It displays the errors:

USB Communication Failure


Error: Target DLL has been cancelled. Debugger aborted

Sometimes the debug session starts once but fails the second time. It can lead to the crash of µVision when trying to restart the debug session.

How can I solve this issue?


The reason, which causes such an issue, is that some specific DLL files for ULINK debug sessions cannot be initialized properly in some cases within Windows 8.x and Windows 10.

To solve this issue, update your MDK to v5.17 and newer versions.




The following Discussion Forum threads may provide information related to this topic.

Last Reviewed: Wednesday, September 13, 2017

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