Flush the DNS:
Copy and paste these lines in Note pad. @Echo on
attrib -h -s -r hosts
echo 127.0.0.1 localhost>HOSTS
attrib +r +h +s hosts
netsh winsock reset all
netsh int ip reset all
shutdown -r -t 1
Save as flush.bat
to your desktop.
Right click the .bat file and choose to run as Administrator. Your computer will reboot itself.
If this doesn't help then look more closely at the logs shown in Troubleshooting Steps for Windows 7
, for networking related errors logged at startup, google the exact text and identifying number of these errors or post back a screenshot of them, to research how others solved them.
Can you borrow a USB wireless adapter to plug in to try with it's driver from disk or the web?
Can we see a screenshot of the Device Manager>Ethernet Adapter Driver tab?