Cannot connect to the internet after a system restore on my laptop?

[redeye069]

I recently got a nast virus/trojan. It completely disabled my laptop. The only thing I could do was a system restore. (Not restore to previous point) I basically wiped the hard drive. Now for some reason I cant connect to the internet. I have it plugged directly into with the ethernet cable but my pc says there is no connection. Device manager says my modem is working correctly, and auto detect connections is on. Wireless can detect a connection but I dont have the password. Its a HP laptop running Windows XP. Any suggestions