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Error message: "Application Error KestrelUI has Encountered an Unrecoverable Problem and has had to Close" - WKB29464

Article number: 29464


  • The following error message appears when attempting to launch the Waters ACQUITY console:
    • "Application Error: Application KestrelUI has encountered an unrecoverable problem and has had to exit."
  • 'MS Detector' is displayed instead of 'QDa Detector' in the Run Samples window in Empower.
  • The QDa Detector is absent in the Waters ACQUITY Console. KestrelUI_error_message.png


  • ACQUITY QDa Detector
  • Empower 3
  • Waters ACQUITY Console


The Windows user account does not have administrator permissions and cannot launch the KestrelUI.exe program that controls the ACQUITY QDa detector; or, the Windows user account does have administrator status but has become corrupted. 


  1. Temporary workaround. Navigate to: C:\Empower\Instruments\Mass Spec\MassLynx\Kestrel.
  2. Highlight KestrelUI.exe > right-click > Run as administrator. This needs to be done every time the PC is re-started.
  3. Ensure that the Windows user account has administrator status.

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