Unfortunately, some email providers are currently blocking email which originates from the MOC (the perceived source of email when you use the provided "E-mail a Member" function). The ISPs which consider MOC email to be SPAM and rejected immediately are:
SBCGlobal.net and ATT.net (basically the same providers)
If a member with one of these addresses is sent an email it is rejected and returned to the originator (not the MOC but the email address of the sender from their Profile) with a message to the effect:
Could not deliver message to the following recipient(s):
Failed Recipient: xxxxxxx@att.net
Reason: Remote host said: 521 DNSRBL: Blocked for abuse. See http://att.net/blocks
-- The header and top 20 lines of the message follows --
Received: from www (www.forumco.com [174.123.0.154]) by mail.forumco.com with SMTP;
Sat, 30 Apr 2011 17:14:25 -0500
thread-index: AcwHg/bVfDFPQu3XTrmT0pF8h8X7Ug==
Thread-Topic: Sent From Montana Owner's Club Discussion Forum by CRAFT-Guy
From:
To:
.....
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The MOC is working with our service provider and ATT/SBCGlobal to remove this blockage of email originating from the forum. We hope to have this corrected soon. In the meantime, members can use the PM function to contact other members or email them directly from their personal email accounts.
Rondo's suggestion to check your Profile is a good one as many members have changed email addresses since they joined.