HitmanPro

Today I was having trouble getting to my email account.  I was finally shown a popup asking if I needed help.  I thought I was dealing with my IP.  I was asked if I would allow a small program installed that would allow a quick check of my computer.  I said OK  - but it turned out to be something called HitmanPro.  Then I got a call from the company on my cell.  I answered saying that I thought they were my IP because the last time I had email trouble it WAS the IP.  The rep of this outfit said that his company uses the HitmanPro for diagnostic purposes and a technician from the company would use the info to correct my problem.  But that for a check of my trouble would be no charge.  After a few minutes I was told that I have almost 1500 malware files on my computer.  And that very likely my email problem will be caused by one of them.  I was told that an estimate for the repair would be around $200.00.  I told this person that I would think about the offer, but did not commit for anything.  I immediately ran a complete check of my system with Norton and found nothing wrong.  In fact I played around further with my email account and eventually got into it OK. 

So what's all this malware?  Is there something else from Norton I should be using to see this malware and remove it?