Avast! Defective antivirus product turns into sucker bait unknown - online only internet

Via the internet I ordered and installed Avast Premier($39.99) on 2/7/14. Apparently it did not install correctly. I kept getting spam from them telling me my trial subscription would soon expire.

I called the support line on 2/11/14 for assistance. I allowed them to remote in to my computer to correct the problem. They told me Avast would not work properly due to problems with my computer (which made no sense to me) and I would have to purchase a service contract ($179!!) to fix it. I told them I'd think about it.

I was suspicious so I searched online and found a number of complaints of a similar nature. I suspected this was a fraudulent scheme because my computer was working OK so I called back and told them I wanted to cancel the order per their 30-day money back option. The first person I reached told me I had to use their website to cancel the order and hung up on me.

I searched their website thoroughly but found nothing about order cancellation. I called support again and explained my experience to another person. She told me she would send me an email with cancellation instructions. 

Later I received an email from them that had another license agreement and installation instructions but nothing about canceling the order. I tried to reply to the email but their system would not accept it.

I gave up and called my credit card company to withhold payment. The credit card company filed my dispute and began an investigation. They ultimately denied my dispute based on a lot of irrelevant information provided by Avast's billing agency ("NEXWAYSOFTWARE.COM).

I'm sick of this blatant ripoff so I'm going to write it off as an expensive lesson. I hope anyone reading this will take heed.