Thank you for contacting Plugable support! Sorry to hear about this issue. I’d be more than happy to assist you.
Have you tried configuring the screens through the Display Settings control panel vs the keyboard shortcuts? Sometimes the Windows + P project settings shortcut doesn’t work correctly in our experience.
If the control panel settings don’t change the behavior, can you tell me what port is this screen attached to on the UD-ULC4K? The HDMI port or one of the DisplayPorts using a DP to HDMI adapter?
Depending on the model of Envy x360 you have, it may not support the HDMI port on the dock as this port requires the host system to support USB-C VESA DisplayPort Alternate Mode video output. In addition, if you’re not using the stock USB-C to USB-C cable that the dock shipped with that could be part of the problem. Not all C cables support the aforementioned “Alt Mode” output.
So I think our first course of action is to determine what exact Envy you have. We have a troubleshooting tool that helps us find out what is going on in situations like this. Please plug the dock into your computer, then go to this page and follow the instructions there:
Please don’t hesitate to let us know of other questions.
Thanks again for contacting Plugable support and best wishes!
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