I am a New Member at Similar Worlds

As TwiddlerOfThumbs said on cost, it took a lot of skill, knowledge, and time on the part of the people who wrote the code and they need to be paid for that. I think it should still reinstall as long it's the same operating system. And like she and Plobey said, you should get regular updates to it. My antivirus has a one year subscription, and as long as I keep renewing it, I get updates all the time.

reinstall your virus protection - I would hope there are updates out there to add onto it that you can download.
And why? You ought to ask those people creating viruses why they work so hard to outsmart all the fixes sold.
Why does it cost so much? You are paying for someone elses knowledge in how to protect your computer. That's why.

I use free versions of MalwareBytes and SpyBot, together with Windows 10 built-in protection. It works well for me, and I've always viewed paid-for like McAfee as "Protection Money"....

I see no reason why it wouldn't work. It is probably outdated and needs a couple of updates, but it should download those automatically just like before.

@Jessie102005 - depends on who produced it and how old it is. Probably not, but it may.

Was that addressed to me, Jessie?

Would updating it cost?