480973 - I own a website and members are not getting email

Status: RESOLVED INVALID

(Firefox :: General, defect)

Description

[Bob]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.6) Gecko/2009011913 Firefox/3.0.6
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.0.6) Gecko/2009011913 Firefox/3.0.6

Members at my website were encouraged by me to switch from IE to Firefox. The site allows them to receive track back emails regarding topics they have interest in. The system works with IE but not Firefox. They are complaining about the problem. I am getting this message:
This is the message we get at the mailserver:
# TRANSACTION FAILED
# 440 - [e-mail] R=fail_remote_domains: The mail server could not deliver mail to [e-mail]. The account or domain may not exist, they may be blacklisted, or missing the proper dns entries.
This member just switched back to IE and is getting tracking emails. Any thoughts? Thank you.

Reproducible: Always

Comment 1

[Matthias Versen [:Matti]]

Why do you think that this is a firefox bug with such a clear error message ?
The mailserver can't deliver the mails to [e-mail] email server. 
Firefox is no mailserver (your or the remote one).

Comment 2

[Bob]

Because when the member switched back to IE it worked again. My aim here is not to be negative about FF, rather to solve the problem. Ergo, why does our site function as intended when a member use IE and not FF? I realize that FF is not a mail server and am looking for solutions not to be patronized. Shall I have all my members delete FF and revert to IE? Thank you.

Comment 3

[Matthias Versen [:Matti]]

You can be negative about Firefox but that's not the point.
The error message is very clear that your server seems to have an issue with sending the mail to the remote server.

From where is the email address like [e-mail] ?
Is that from a form submit or from some Account properties (database). 
A form submit could introduce something from Firefox like a invisible char, for example a carriage return or something like that.

Comment 4

[Matthias Versen [:Matti]]

invalid as this isn't a firefox issue