How to make all multimedia keys work?

Question

Iron

Good evening. I bought a SVEN Comfort 4000 keyboard. Out of 14 multimedia keys, only 10 work. I need to make all the keys work and redefine the standard ones. Tried different programs, including MKey, nothing helps. All non-working keys MKey recognizes as one. How can this problem be solved?
// The keyboard is terrible, I do not recommend it to anyone

Answer 1

The FAQ on the manufacturer's website says:

Additional (multimedia) keyboard keys do not work. What to do?
In Windows OS, follow the path "Start" → "Control Panel" → "All Control Panel Items" → "Administrative Tools" → "Services" or call the command line (key combination Win + R), type "services.msc" and press the key Enter. Locate the HID device access line. The status column should read "Working". If this is not the case, right-click to open the context menu and select "Properties". On the General tab, click the Run button. Set the startup type to "Automatic" so that the service starts when Windows 7 starts. On the "Recovery" tab, in the drop-down lists "First failure", "Second failure" and "Subsequent failures", select "Restart service", then click OK.

Tried?

Answer 2

SVEN Comfort 4000 compact keyboard has such special features as modern slim design, comfortable volume control, wrist support, 10 shortcut keys for Internet and Multimedia , 3 keys to control power supply to PC , low operation noise level, quiet and precise keystroke.
Description on the website