500 Unauthorized relay msg rejected

[Mctabish]

I have been randomly getting this message. It i _DOES NOT SEEM_ to be isp
related (tried from work and or home, this is a laptop) I have tried this
through different accounts - Usually, Once I get this error with an email, I
will NOT be able to send that message, but if I recreate the message, it
usually will go through.
In this case, I was sending this to myself...
What could be causing this?

Thanks
Mc
sample error:
Your message did not reach some or all of the intended recipients.
Subject: Emailing: ordersuccessful.htm
Sent: 12/20/2005 6:16 PM
The following recipient(s) could not be reached:
Mctabish on 12/20/2005 6:16 PM
500 Unauthorized relay msg rejected

 

[Thomas Quester]

You need to check "This server needs authentification" in your email account
under the SMTP tab.

Thomas Quester
www.olfolders.de

 

[Mctabish]

Thanks!
It has been my understanding that this would be a CONTINUAL problem if that
is that case. Could it also be random?

I will check the boxes!

Thanks!
Mc

 

[Brian Tillman]

It has been my understanding that this would be a CONTINUAL problem
if that is that case. Could it also be random?

Usually not random, but if you have more than one account and you send a
message with an account whose address is in domain X using domain Y's mail
server, you'll see the problem. As you move your laptop from one place to
another, the ISP you're using changes. When you're using an account where
the sender address domain matches the ISP, the mail goes through.
Otherwise, it doesn't.

 

[WiggleRoom]

I have had the same problem. I check the authenticate boxes. None of my ISP's
match the pop domains but I have been successful sending before. I monitor
multiple email addresses from one Outlook profile. I like to respond to
emails with the same domain they sent the email to. It seems to work from one
partition but not from the other (same ISP). Settings are all the same. Any
thoughts?