To factory reset an RC-03, RC-04, or IP-Bridge; you will need to hold the reset button down for approximately 15 seconds. The location of the reset button differs from device to device.
RC-03:
Small horizontal button above the RJ-45 input.
RC-04:
Small round button on the back of the device (center). You will need a paperclip to press this.
IP-Bridge:
Small round hole on the right side of the device. You will need a paperclip to press this.