When you say your box won't turn on, do you mean there seems to be an issue of no power and the box will not power up?
Or do you mean there's something going wrong as part of the bootup/startup sequence?
You can try leaving the box powered-off at the mains for 5-10 minutes, and then switching it on. Assuming all connections are finger tight, and the box is suitably connected to your homehub for the internet, the box should startup on perhaps 10-15minutes.
If that's failing, your best point of contact is TV faults. 150 from your Virgin landline, or 0345 4541111 and follow the prompts for "I have a fault with my TV service"
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