Hello,
Yes you have been infected by a virus,
Ok what i would recommend is go to this website http://www.ewido.com/ and download the AVG 7.5 Spyware Software (this is a free download) Once this is downloaded and ensure all updates are downloaded on this and your Antivirus software.
Now lets reboot your computer and as your computer is rebooting tap the F8 key continuosly this will bring you to a boot menu and choose safe mode. Once your system boots up completely run a full scan again with your Norton antivirus and the AVG spyware software.
Once this completes go to Start - Run - type in without the quotes "del *.tmp/s (there is a space between the del and the * symbol) and hit enter. This will clear out all of your temporary files.
Once this completes close out of all windows and reboot and see if it is running correctly now.
Hope this helps,
Thanks
Rita
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