when i open up my finder, i can see their computer name under "shared." any advice?
It does.not sure but I don't think that means they're on our network
First you should make sure that outside machines are actually connected to your network. You can use the Airport Utility to view a list of current and previous wireless clients.
If they are in fact using your network, you have a few options available like using a more advanced encryption and MAC address filters.
I'm assuming you're not using WEP.
If you're already using WPA/WPA2, don't change it. WEP is an older encryption method that should only be used as a last resort.
To see which clients are currently logged on to your device, go to the Airport Utility application, select your Airport Express in the left column, choose Manual Setup at the bottom of the window, select Advanced at the top of the window (next to Printers), and select Logs and Statistics at the bottom. You can then choose between Logs and Wireless Clients. Wireless Clients will show you all devices currently connected to your Airport Express. The Logs selector will show you any previous devices that have accessed your device (in the form of a MAC address).
Do that first to determine if there are actually unauthorized devices on your network.
When is the last time you've changed your wireless password?
Double check to make sure your MAC address matches the one on the list. You can click on the Airport icon on the menu bar, select Airport on the left, click Advanced and your MAC address should be listed next to Airport ID at the bottom.
You can also scan the logs on your Airport Express to see if any other clients were connected recently. Keep in mind they might be some of your friends if you've shared your wireless password with them.
The Airport icon in the menu bar at the top of your screen. The button you use to select which wireless network you want to connect to, not the Airport Utility you've been using to check the wireless clients.
Also, is your Airport Express your primary wireless access point? Is it connected directly to your modem?
no it is connected to a jack in the wall that my apartment provides. i just checked my network preferences, then went to advanced, i see my apple id but nothing else...is that normal?
Chances are, your machine is the one listed as a wireless client. Also, if you have shared a network at any point with another computer (possibly a friend), their shared folders can show up in Finder. It can take some time for those to go away.
If you click on the shared folder you're seeing and you aren't prompted for log on credentials and no files or folders are listed, the share is probably no longer attached to the same network as you. Have you tried rebooting?
The Airport icon in the menu bar at the top of your screen. The button you use to select which wireless network you want to connect to, not the Airport Utility you've been using to check the wireless clients.
Also, is your Airport Express your primary wireless access point? Is it connected directly to your modem?
You can also try this:
Click on the Spotlight button (magnifying glass) in the top right corner. Type Terminal and select the object next to Top Hit called Terminal.
Once that loads, typeifconfig en0
Your MAC address will be listed next to "ether".
when i click on his macbook, it has a public folder that i can enter, then one drop box folder, but that drop box folder will not open when i click it. it says that i dont have permission to see it's contents...not sure what that indicates!
So are you plugged into the wired LAN? Is the wired LAN shared with neighbors?
I'm guessing this is the supposed problem.So are you plugged into the wired LAN? Is the wired LAN shared with neighbors?