@Jim1Eng,
Your network should be able to recover from a power failure whenever one occurs. However, in the event of the network not recovering, there are a few things that you can try:
Remove the Ethernet Cable between the Modem and Main Deco without removing the device's power, then wait 5 minutes and reattach the cable to the deco.
If the main node is providing a connection, try simply power cycling the satellite nodes so that they can rebuild the backhaul.
A few Questions:
What is the LED Status of the Main Deco Node? Of the Satellites?
How is your Desktop Connected to the Deco?
If your PC is bypassing the Deco Network and connected directly into the modem, make sure that this connection is removed and the PC is connected to the Deco Network, then try to perform MAC cloning for your PC, as this may be preventing the connection.
If you have multiple decos, you could try to take one of your satellite nodes, and place it as the main node. If something happened to the individual unit during the power outages, this may be an easier fix than having to reconfigure your entire network.