i know this thread is old, but please someone please help me!!!!

ok my main computer was having problems so my dad disconnected the hard drive and went to fix it. the guy said it was a virus and cleared it. the guy changed our windows vista to windows xp. everything including the the internet was working fine. but i wanted to change our windows back to vista. i used a vista transformation pack but then a day later i deleted it. then i went to search online to find another program but i was dissatisfied so i deleted that too. but after i deleted that, the internet suddenly didnt work. the internet connection said 'acquiring network address.'

on my brother's laptop (the one i used to reply this post) it said 'acquiring network address' for few seconds and then it worked (the internet). on my main computer, i also checked the connection status and it said this:
Address Type: Invalid IP Address
IP Address: 0.0.0.0

i also tried repairing the connection but it said this: 'Windows could not finish repairing the problem because the following action cannot be completed: Renewing your IP address'

can someone please help me!!!!!