Cannot access MyBookLive suddenly?

From manual…
Power On - Blue - Solid - Displays when you first apply power to the unit.
For other colors see manual.

If it does not get pass that color, you have a bad unit, either enclosure, drive or file corruption. That is assuming you have the ethernet cable (RJ45) plug in.

You have two options:

ADDED:
Blue could also mean standby. But if at boot it does not get pass that, it is not good.
If at any time you also have green, then go to whoever you DCHP server is, which is usually the router for home networks and check the DHCP lease table. If MBL is listed there should be an IP next to it, try to access the dashboard by typing that IP in a browser such as “http://192.168.0.101”. Replace 192.168.0.101 with the IP from the DCHP table.