The NAS-7400 worked OK until I turned it off. When I turned it on again, my Windows network drive connection no longer works.

When you powered up the NAS-7400, the DHCP server assigned a different IP address to the NAS-7400. Here are two possible solutions:
• You may be able to reset the NAS-7400’s IP address manually. Note that changing the NAS-7400’s IP address may cause an IP address conflict on your network. Check with your Network Administrator before taking this action.
• If you cannot restore the previous IP address, you must create new network drives and printer connections.