Nortons AV excluded files puzzle

[kissyone]

Hi.. looking thru my nortons avirus options I saw that two file extentions are excluded from being scanned for viruses.. *.nch and *.dbx (both Outlook Express files I think)..... I didn't exclude these so if I didn't put them in there how did they get there.. hmmm? I have OS Windows 98se... Do I have a worm that is on my pc and don't know about it? When I delete these extensions from the exclusion box and then click DEFAULT, they return into the exclusion box... Please help if you can..... I also posted note about two ports (23 and 80) being open could this be anything to do with this latest problem I've found... (silent scream). Any ansa's on this one guys please - would sure like to sort this out? Thanks in advance for help.