can't find or remove virus - using Norton Security Suite
I hope someone out there can help. I believe my laptop has a virus. For several weeks I've been having trouble with it getting hung up and becoming completely unresponsive so that I have to hit the power button to shut it down. Have also been having problems getting it to start up. I have tried lots of things to try to solve this, but it keeps recurring. Then, in the last few days, bogus e-mails have suddenly started being sent through our comcast email account. I use outlook for email and have 2 email accounts set up through outlook - one is my comcast.net address, the other is NOT a Comcast.net address (it's an address I set through my web host). All the bogus emails have been sent through the comcast.net address and not the other email address, and the addresses that they have been sent to are from the address book on the comcast server, not my address book in outlook. I have run multiple scans on my laptop using Norton Security Suite and it has not found any viruses. Also downloaded and ran Malwarebytes, it also found nothing. I tried to run Norton Power Eraser but could not get it to run - tried several times, even tried the BETA, but could never get either to run. I kept getting an error saying that it was missing definitions needed to run the program. I'm not sure what else to do or try at this point. Can anyone help? For the record I am running Windows XP on the laptop and unfortunately do NOT have XP install disks.
I Should also mention that we also have a desktop computer that could potentially be the virus victim, but we are ssuming that the virus is on the laptop since it has been acting up lately and the desktop has not.
A couple more things to add: When I look at the NIS security history, I see quite a few entries labelled "medium" risk. For example from 9:54 to 10:01 tonight, there are 6 entries labelled "Unauthorized process blocked (access process data)", and I saw many similar types of entries earlier in the day. I also saw this entry at 3 am in the security history and have no idea what it means, but it sounded fishy:
"Protecting your connection to a newly detected network on adapter \"Intel(R) WiFi Link 5100 AGN - Packet Scheduler Miniport\" ,Detected,No Action Required,Firewall - Network and Connections
Thanks to anyone who can help!!