The Ui24R and the connected HDMI device need to be able to recognize and communicate with each other. This is the “HDMI handshake".
The “handshake" not working most often results in not being able to see anything on your monitor.
Before frustration sets in, there are some things you can do yourself, if you find that your HDMI-connected components are not communicating properly.
Double-check The Physical Connections
Make sure all cables are connected as they should and you have selected the correct input in your monitor's settings menu.
Try A Different Turn-on Sequence For Your Components
If you turned on your monitor first, then your Ui24R, try the reverse turn-on sequence and see if that works. Once you have determined the best turn-on sequence - write it down for future reference.
Check The Resolution of Your Monitor
Ui24R output resolution is fixed at 720p. Check that your monitor is set to the same resolution as well. Most monitors automatically scale to the right resolution although some need manual selection (Source Device's Video Resolution Output Setting).
Troubleshooting HDMI-to-DVI or DVI-to-HDMI Connection Problems
HDMI-DVI conversion can cause problems. If your monitor has DVI input, it needs to support HDCP. This allows communication between HDMI and DVI devices. You can also run into a situation on older DVI-equipped TVs that even if they are HDCP compliant, they may not have the proper firmware to recognize the identity of the HDMI source component you are trying to connect. An active HDMI to DVI or HDMI to VGA adapter normally works better than a passive one.