Desktop all in one won’t restart

[Cinderella3]

I shut down my new desktop before vacation. The Start button is on bottom right. When pressed I only got symbols on lower right screen. When start button pressed again, got some square with setting info like brilliance etc. mouse wouldn’t work. It shuts off every time.I looked up manual, and  Unplugged, and tried restart. Pressed button 15 seconds, tried control/ alt/ delete. Same symbols etc! How do I get to my start screen? 

[Grzwacz]

Hi,

Okay, you do get display output (symbols on the lower right screen).

Do you have LED action on the AIO chassis like power LED or HDD activity LED? Do you hear any startup sounds like HDD sounds or DVD sounds?

Contact HP support (Link) if in warranty, you stated this PC is new.

You could have a external power supply problem or other hardware problem if the PC display works but the PC can't POST. Have you tried starting the PC, tapping "ESC" to see if you can get to the HP UEFI Startup Menu?

We could run hardware tests if you can get to this menu.

Regards