Ok, what you need to do is go to start > Right click on My computer > Properties.
Click the Hardware tab, then click Device manager. Now, you SHOULD see a "Network adapters" in the list, If you see that, with the problem you are having, there should be a yellow question mark/exclamation mark. If you do see that, right click on it, and click properties.
You should see the following message.
"The drivers for this device are not installed. (Code 28)
To reinstall the drivers for this device, click Reinstall Driver."
Now, Find out what kind of ethernet card it is, by downloading Belarc Advisor
Belarc Advisor - Free Personal PC Audit
After you find out what kind of ethernet card it is, google something like this.
"HP EN12070-TX PCI 10/100 Driver download"
Download the driver to the desktop, then remember when we right clicked on that network adapter that had the yellow question/exclamation mark?
There should be an option right there to "Re-install driver" If not, click the driver tab.
Once you are at the reinstall screen, click "Install from a list or specific location (Advanced)
Now, click next, then check the "include this location in the search"
And then hit browse, go to wherever it is you saved the driver, and hit next. It should now let you connect to the internet.
If this doesn't help, MSN me later today, I'm off to school
Hope I helped