I'm having a slightly different problem and was wondering...

[richardg1]

@shaw-tony I'm having a slightly different problem and was wondering if anyone could help clarify it.

We email a few hundred Shaw customers weekly using an email list management system. Once in a while an email address will bounce with a 550 error code. If I do a manual SMTP request a week later it works fine, and when we get the email address re-activated on our platform we can email them again.

I'm not sure what could cause these intermittent bounces. Unfortunately it causes some people to miss emails they were expecting and it can be a few months before we get a complaint and detect the problem.

Everything else sends with no problems.

[mdk]

@richardg1 -- from a non-Shaw web-site,

Here are some possible causes for email error 550:

1. Your email address has been compromised, and so is blocked by the recipient's mail server.
2. The recipient's email address doesn't exist.
3. The recipient's email address is temporarily unavailable or suspended.
4. The recipient's hosting server is temporarily unavailable.
5. Your domain name is invalid or blocked.
6. Your internet gateway has a firewall or a filtering feature which mistakenly identified your email as spam and blocked it.
7. Your email is mistakenly identified as spam by the recipient's mail server.
8. You are using your email client from a different IP address.
9. The recipient's mail server failed to identify your email address.

Doing a Google-search for "SMTP error code 550" will give you lots of web-pages.

Maybe, it is just a "mailbox full" message on the recipient's mail-server ?

[richardg1]

I am asking about Shaw specifically since we see this much more frequently with Shaw email addresses than any other domain.

One day we will get the response "550 5.1.1 xxx@shaw.ca recipient rejected".

The next day it works fine.

This screws up our email platform since it is an unexpected response, and requires manual intervention when we notice the problem months later.

The error message does not indicate whether it should be considered a temporary error.

[mdk]

@richardg1 -- The error message does not indicate whether it should be considered a temporary error.

Correct, but the error code -- 550 -- which should be interpreted as "5.5.0", does signify that is a permanent error.

A temporary error is usually "invisibly" handled by your outgoing mail-server responding to a "temporary" code by requeuing the message, waiting a short time (1 minute? 5 minutes?) before retrying to send the message to Shaw's mail-server. After some number (10? 20?) of failed attempts, your mail-server will call it a permanent error.

> The next day it works fine

I would still bet on "mailbox full" causing a "permanent" error, and the recipient noticing that the flow of incoming messages has stopped, and the recipient then empties their "trash" folder, and deleting other messages.

[JKA1965]

Hi Tony, 

I have been having a similar problem with emails to shaw not going through.  I have a business website hosted at greengeeks.com that has an email address and any email received there is to be forwarded from that site to my shaw address. That isn't happening and the problem appears to be at Shaw's end. 

I have also tried sending several emails from the website email to shaw (a few different shaw addresses) and I receive the same error messages each time:

A message that you sent could not be delivered to one or more of its recipients. This is a permanent error. The following address(es) failed: xxxxxxx@shaw.ca

all hosts for 'shaw.ca' have been failing for a long time (and retry time not reached)

Reporting-MTA: dns; mtl103.greengeeks.net
Action: failed
Final-Recipient: rfc822; xxxxxxx@shaw.ca
Status: 5.0.0

However, when I send an email from gmail to all those shaw email addresses, it goes through without any issues. Greengeeks techs looked at the email logs and the error is coming from shaw. So why are the servers at shaw giving incorrect responses to the servers at greengeeks.com? How can this be resolved?