I have an email list of about 500,000 users. This was an opt in list that I have built up from my niche sites over about 7 years.

The list was down to about 313,000 when I was sabotaged and lost my backup of my email list.

Now all I have is my original 500,000 list.

I need to get rid of all of the email addresses in it that are no longer valid. The ones who opted out are just going to have to get another email from me and opt out again I guess. I don't know what else do to for those people but apologize.

Any email verifier software that WORKS would be great. I bought one but it doesn't work, and support just blamed it on my firewall and/or antivirus which I disabled and then of course they just couldn't help me...