Windows server 2016 Activation stuck at 10% for over 12 hours
The problem each time was that the Windows License Manager Service was not running. By default the service is set to Startup Type: Manual (Trigger Start). I believe dism.exe is failing to trigger the service to start, thus halting the process. Simply starting this service, while dism.exe was stuck at 10%, resolved the issue 100% of the time.