[Dave]

I found some information on this page: https://postmaster.aol.com/error-codes (under "other errors")

Originally Posted by AOL

AOL will not accept delivery of this message
This is a permanent bounce due to:

• RFC2822 From domain does not match the rDNS of sending server.
• RFC 2822 FROM address does not have an A record and is not a valid domain.
• IP has a poor reputation and mail is sent to multiple recipients.
• There are multiple From address in the mail headers and the IP reputation is poor.

Maybe that will help you out.
If that doesn't help you out, you can attempt to create a ticket here in order to reach out to AOL. (under "other issues")

I would also do a blacklist check here: http://mxtoolbox.com/blacklists.aspx and run diagnostics here: http://mxtoolbox.com/diagnostic.aspx. That shows that your reverse DNS is not a valid hostname.

Originally Posted by mxtoolbox

Your Reverse DNS Record (PTR) is not a valid host name. According to email sending best practices, a PTR Record should be a valid host name. If the PTR Record is not a valid hostname, there is a likelihood that you will experience email delivery issues with anti-spam services.