Presents as: After completing a firmware update the camera is no longer responsive.
Try power cycling the camera by unplugging it for about 30 seconds and then plugging it back in.
If you have an extra power cable and/or adapter, switch those out to see if that alleviates the issue.
Try plugging the camera into a different power outlet.
Attempt a factory reset, and try to set up as a new device:
Cam v1, Cam v2, Cam Pan: Remove the SD card if there is one inserted. Hold down the setup button until the status light turns solid yellow. Once the status light begins flashing yellow, you may attempt to set up again.