I have a user who states that he has registered with our Forums, but has not received the Forum generated e-mail with his password. I went into the Admin section and requested that his password be e-mailed again.
I received this message as a result (I put the "xxxxxx" string in):
Your message did not reach some or all of the intended recipients.
Subject: Password for COADE Discussion Forums
Sent: 2/22/2007 8:37 PM
The following recipient(s) could not be reached:
xxxxxxxxxx@rediffmail.com on 2/22/2007 8:37 PM
There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.
<S59178 #5.5.0 smtp;553 sorry, invalid HELO hostname (#5.7.1)>
I've received a number of these messages over the last several months, with the common thread being "rediffmail.com". I just blew this off at first as some sort of spam nonsense, but now a legitimage user is e-mailing me from this domain.
I've read other posts here, that state the ISP on the other end could have some filters in place. What can I advise the user to look for? What advice should I request that he pass on to his ISP? (I just can't imaging what in the password e-mails would get trapped by a filter ...)