How Do I Get DDO (Dungeons & Dragons Online) Operational On Windows 10 Desktop?

The Situation:

The game was downloaded and installed normally via Steam. With installation complete, I clicked the "Play" button from the Steam window. The launcher for DDO appears, then performs necessary downloads. When I click to launch the game (regardless of server), the launch window disappears and then...nothing.

Steps Toward a Solution:

• In task manager, I did not find any programs running (after clicking to launch the game) that relate to either DDO or Turbine.
• Rechecking the minimum system requirements, the computer in question is well-above spec.
• I read this question about running on Windows 8.1, but unlike the OP I receive no error messages at all.
• Per this DDO support article, I checked for scheduled downtime - such was not the case.
• Per the same article, I checked the files mentioned therein - everything was correct.
• Continuing to follow suggested troubleshooting, I made sure to launch as an Administrator - still nothing.

In the next room on a different computer, without any special attention or modification, the game launches and runs without the slightest hiccup. As to finding a resolution, I am currently stumped.