I have lost the internet connection from my log in ?

You may have a rogue scareware AV that's trying tou coon you into paying to install a trojan malware. It's probably trying to prevent you from getting a real AV.

Try to restore your system to a previous restore point.

From another computer, download one of those antivirus and place it on a removable media:
AVG Free
Avira
Microsoft Security Essentials

Install it on your computer and do a full scan.

Also, get Spybot Search & Destroy.
Install it and do a full scan.

Electro
May 2011