Network dropped on wired ethernet

Question

The other day I was browsing along the internet, when suddenly, Shiira notifies me that I'm no longer connected to the internet. Sure enough, my iChat connection was dropped as well. Since then, I haven't been able to connect with wired ethernet.
The cable's fine- it's plugged into the PC I'm using right now. And since I can connect fine from here, I assume my cable modem is fine as well. I'm not using any sort of router.
I tried fiddling around with my network settings, though my knowledge in that area is extremely vague. I pretty much just did what the "Assist me!" button said. That didn't work. I always dread it when my computer tells me to contact the ISP to find out what's the matter.

Answer 1

Typically there's not a lot of setup needed to get a Built in Ethernet connection working.
Do you know if it's a cable or DSL connection? If DSL, do you know what the username and password might be?
One thing you could do to check is to Click on the apple in the top left corner and click on "About this Mac". Click on "More Info" and there should be an entry down the left side of the system profiler window for "Network". There's either an entry below that for "Built in Ethernet" or it'll list it when you click on "Network" itself. Basically, I'm looking to make sure the harware is still recognized, as it's strange a hardwired connection would just drop off.
Once we know that the hardware is still working I'd do the following.
1: Unplug the ethernet cable from your computer
2: Trash the /Library/Preferences/SystemConfiguration folder and restart your computer
3: Upon restarting your computer, click on the apple and go to "System Preferences"
4: Click on the "Network" item
5: Change the "Show" selection box to say "Network Port Configurations"
6: Drag Built in Ethernet to the top of the port list
7: If you have a DSL internet connection that is a PPPoE connection type, then change the "Show" selection box to "Built in Ethernet"
8: Go into the PPPoE tab, check the "connect using PPPoE" selection box and enter the appropriate information
9: click on "apple now" in the bottom left corner
10: Plug in your ethernet cable and restart the computer
If you are not connected after restarting we've narrowed out the possibility of it being hardware related and also ruled out the fact that there could have been any corruption in the SystemConfiguration folder. If you're still not connected, change the "Show" box in Network preferences to "Built in Ethernet" and go into the TCP/IP tab to see if you have an IP address...if so, what is it?
Sorry for the long post, but internet connection issues are always fun.
You can always just reset your modem after going through that whole ordeal with the network preferences.
I dunno, let us know if you get anywhere.
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