MiFi2200 has a red flashing light and will not get a signal. When it's plugged into the wall, the button light flashes red. When I plug the device into the computer, Verizon manager doesn't detect the device.
You may have discovered by now:
"Red Blinking The battery is critically low."
Leave it plugged in for a while.
The LED can be Green, Green/Yellow which the book calls Amber, or Red.