I believe that our site was black listed because I used to host it in Russia. The previous owner of the IP address probably hosted some sort of Malware on it, and Avira blocked all domains that used/use that IP address.

We do not host Malware. The server that hosts our main website is located in the United States, so if we were hosting Malware we would have gotten shut down.

I will contact them now about the issue.

Thank you for informing me.