Just received this device and stuck from start

switch it on.
No new wifi network in air....
connect pc to any port (LED shows that PC connected) - DHCP doesn't assign any address.
try to reset (3 and 5 seconds hold reset buttons after start) - no success.

I have no idea what to do...

Try to google Winbox

Netboot & update firmware with default settings helps to start it. Interesting why it doesn't work from the beginning....

The default configuration does not have DHCP service running. You'll need to use Winbox and connect via MAC address.

Default-config script on shipped version doesn't set up the router fully, it applies IP address 192.168.88.1 to ETHER1 and that's about it. Use mac-winbox to connect and setup to your liking.

Alternatively you can try upgrading to latest version and resetting to factory defaults again, maybe the new version fixes the default config.

Good luck