Our ColorQube 9303 can't get up. It was turn off with main power switch at the end of one day and when we turn on with main power switch it freezes at loading screeen and nothing happened.
Do you have any advice for me?
Unplug it for an hour and try again.
Failing that, do an Altboot (copy the usb method/process he uses, use this firmware for yours) to fix it if it is software that is the problem (It will wipe your data, so you will need to set it up again when it comes online)
If it is a hardware failure caused by a surge, you would need to get out a voltmeter and start troubleshooting the hardware, which is impossible for us to help with here due to complexity.