Problems

[Aspvaegen]

I cannot start my keyboard

[Bill_To]

Greetings @Aspvaegen 

Welcome to the HP Forum.

Check for a keyboard on/off button.

Or remove any non-conductive material isolating the keyboard batteries from the keyboard power contacts.

It is possible you may have a faulty wireless keyboard if the wireless mouse works.

If possible, use a wired USB keyboard is you suspect the wireless keyboard has a problem.

Regards

[Aspvaegen]

Thank U for your answer:-) Where do I check for a keyboard on/off button?

[Bill_To]

Greetings @Aspvaegen 

My pleasure.

I would not know where the HP keyboard on/off switch might be. Did the HP mouse have an on/off switch?

Check the entire keyboard.

The on/off switch on my Logitech mouse is located at the bottom of the mouse near the Laser.

Regards

[Aspvaegen]

The keyboard designation is HP 510SP

[Aspvaegen]

When I try to boot I get the message "keyboard error"

[Bill_To]

Greetings @Aspvaegen 

Check Here for a HP keyboard and mouse quick setup guide.

Maybe you have a faulty keyboard.

Regards