You have malicious hyjact entry in your startup registry.
You need to get into windows to remove this.
Try rebooting and hold f8 key as soon as it reboots.
Select safe mode .
Then when up and running in safe mode, start / run
msconfig.exe and select diagnostic startup and reboot.
This will load only microsoft services.
You need to set your internet connection to be firewalled.
Need help? Open help and support and search
for "firewall" and turn it on
The only way I now to safely remove isass.eexeit is with
hyjackthis. Its free and You can downloaded
at<
http://forums.spywareinfo.com/index.php?showtopic=227>
Run a scan. The entry in Hijackthis should look like
this...
O4 - HKLM\..\Run: [Services] Isass.exe Check the box and
run fix.