02-16-2011 01:20 PM
What is the model and part number of that computer? They look something like "Satellite C640-1007U" and "PSC02L-002003" respectively. Or maybe it's a Satellite Pro?
We would also need to know which version of Windows (including the bitness) you have.
In the meantime, in case you have an Atheros Ethernet NIC and Windows 7 you might try this driver.
Atheros LAN Driver for Satellite C640, Win7 (32bit), 06/08/2010
Atheros LAN Driver for Satellite C640, Win7 (64bit), 06/08/2010
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