And not a sign there is any issue with your laptop. Since this issue has been with us for over a decade I bet you wonder why.
Did you try changing the Wireless DHCP address reservation, range (that's in the router by the way) or tell your apple laptop to forget this network and do over (on the laptop?)
I've given you 3 ideas and sadly a clue this is one very old issue. It makes you wonder why this old issue is still with us. I know why.
Bob
MacBook Pro 15 in. OS X 10.8.2, NVIDIA GeForce 9400M 256 MB
Problem Connecting.
"Another device on the network is using your computers IP address ( numbers here)(***.***.*.**)
Try connecting again later. If you continue to have problems, change the IP address of this computer or the IP address of the other device. Contact the network administrator if you nee more information."
I get this message every so often on one of my MacBook Pros, more on one than the other.
What can I do to stop this from Happening? I turn off my Mac router and back on that fixes it but I don't want to do this every time I wake my computer.

Chowhound
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