We advise running through the following checks. Does the Red light under the Power Button on the remote light up brightly on the remote when you press any button on the remote? It should be bright enough to see in a brightly lit room. Ensure that you are holding the remote to point at the front of the DVR+(CM-7500). Ensure that the infra-red window on your box is not covered and that the remote control is within operating range. Check that the batteries are not discharged and are in good condition. Try removing and replacing the batteries and making sure they are inserted in the correct orientation. If this fails, please replace the batteries in the remote control.
Note; If you have the second generation remote control, (kind of hour glass shaped with the 4 colored buttons across the top, not across the middle.) when you receive it, it is set to perform a macro command for Samsung TV's and the DVR+. The power command is sent to the TV first. When you let go of the power button, you will see a 2nd red blink. That is when the DVR+ power command is sent. Please keep pointing the remote at the DVR+ during that 2nd blink.
If you have broken or damaged your remote control, or you'd like to have another, you can buy a replacement at www.channelmasterstore.com
You can find the Quick Start Guided and User Guide here.