This is most likely a virus/malicious attack as: 1. The message claims to be from appleboxasia.com, then then has a message ID from yahoo.com 2. It claims to be sent from yahoo.com's webmail, but the hand-off mail server is actually from a Time Warner ISP account 3. The attachment is being detected ...

It's been a while, but most email servers will or can be configured to also accept "mailbox@[192.168.1.1]"-type addressing. Another possible option is to setup a local caching DNS server within the environment too.

Maybe your new provider is also hosting spammers (e.g. H.E. - the folks that use them know who they are). You might run the assigned IPs against the blacklist lookups to ensure they are not listed.

That is a general error message which could be the result of a bad address, mailbox full, mailbox locked, etc. Your best bet is to contact the remote administrator/postmaster for further assistance.

Binary attachments are typically text-encoded while in transit across an email system for cross system compatibility. The text-encoding renders the binary payload non-executable, so it does not execute in that state and is harmless to the transit email servers. The attachments are typically decoded ...

Can you telnet to your server on either port 25 (SMTP) or port 110 (POP)?

You might consider testing with something other than Outlook to rule it out first.

Your server can be practically any valid name that you wish for the MX record as long as it leads back to an actual server which responds on port 25 for incoming SMTP.

abacabb,

The "nature" of the subject site (tabooexchange.com) might also be of issue for some. That is purely subjective and not technical, but some folks may have different positions on its content, thus may decide not to "play nice" due to their viewpoints.

http://forum.mailenable.com/viewtopic.php?f=2&t=11712
http://forum.mailenable.com/viewtopic.php?f=2&t=14836

It's typically a combination of header and message content analysis. Sometime something as simple as an email signature can be a tipping point based on current spam trends (which do change, so the algorithms/scoring adjusts accordingly).

I see your point. Verizon has multiple Verizon sites which state opposing information, which they refuse to address even when the URL is presented to them.

Posting #6 of this thread. A lookup/evaluation tool put them on the rDNS trail, not necessarily Hotmail.

Your statements seem to be limited to finite experiences. This is not a negative dig, but just a comment that there is a bigger world out there... Qwest who is not generally known to be the best ISP out there has a self-service portal for their business DSL service that allows/facilitate the setting...