Is someone on my home network?


macrumors 68000
Original poster
Sep 20, 2007
38°39′20″N 27°13′10″W
Yesterday on two occasions I saw on the "Shared" list in the finder a computer appear!

It was just listed as its MAC address.

First time I've seen this happen,

It wasn't the MAC address of my iMac, (or my iPhone, though that wasn't on the network at the time anyway.

I opened up airport utility and there was nothing I could see logged on to the wireless network (with WPA2 security)

I tried open (click) on the shared device and it was disallowed as I didn't have the privileges. Info just said it was a PC, then it logged itself off.

My current setup is:

ADSL modem/router connected to internet and acting as NAT, supposedly with hardware firewall on. A Time Machine connected to the ADSL, in bridge mode, with the wireless network (with WPA2 security, I never bothered to turn on specific MAC access.)

I'm careful, I think, about what I install, and don't thing I've installed a Trojan, though could this do this?


macrumors newbie
Nov 16, 2009
Hi wackymacky,

its difficult to tell for sure with the info you have provided though it does sound like someone is piggybacking on. If I were you I would restrict my wireless access by Mac Address. You could also switch off DHCP and have give everyone a static IP address and again restrict access by IP address as well. I'm sure there are other things you can do to tighten up security and others may have better suggestions. In the interim go with restricting the mac addresses... I know this can be a pain in the arse though if you have guests that frequently connected to your wireless network. Guess thats one of the trade-offs... Security vs Convenience.

Hope this helps


macrumors regular
Jun 22, 2009

I do not think it was anyone on the network, but the Router,

With the TC there is an smb setting (Windows Sharing) You may have that on that is a cause for that, I have seen it happened and making that go off makes that problem go away, I would try that,

But my network is not even encrypted and never had some one in it, that may be because I like like 90ft from my close neighbour and its an old lady
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