Improve company productivity with a Business Account.Sign Up

x
?
Solved

Intermittent 5.5.0;550

Posted on 2014-02-11
3
Medium Priority
?
160 Views
Last Modified: 2014-04-28
Hey everyone,

I'm having a little trouble narrowing down the cause of an intermittent mail flow issue for a client.

A few times a week, an external user receives a bounce-back from my clients mail server, here is the important information from the bounce-back message:

There was a SMTP communication problem with the recipient's email server. Please contact your system administrator.

<mail.remote.com #5.5.0 smtp;550-(mail.remote.com) [98.X.X.X]:1939 is currently not permitted>


Obviously the client's actual domain is not "remote.com", this is merely a placeholder. Also, while the mail may get rejected randomly, waiting a few minutes and re-sending appears to work for the time being.

Pertinent information about my client:

1. My client's internet connection is currently under fairly heavy load, which does increase their MX server's response time. An upgrade is already being looked at for the connection, we're waiting on the ISP.

2. I have received no other complaints from my client regarding external e-mails that are getting rejected or not coming through.

3. My client uses MXLogic, however, I have verified via a mail audit and a phone call with their support that these e-mails are not getting rejected by them. In fact just to be safe, I've added a *@domain wildcard and a specific entry for the user (redundant, I know).

Pertinent information about the remote sender:

1. I setup a PRTG probe to monitor SMTP traffic on their MX server, it can spike up to 1800ms response time at certain times throughout the day (usually 0830-0900) and is averaging out at 300ms. However, I was not able to match up any bounce-backs to any spikes on their mail server.

2. I called the remote sender's IT company and they did not report any issues.

My Current Theory:

Due to the stress of my client's connection and the stress of the remote sender's server, perhaps this is just too much delay and is causing a timeout.

If you need any more information from me, please let me know, thanks!
0
Comment
Question by:menreeq
  • 2
3 Comments
 
LVL 31

Accepted Solution

by:
Gareth Gudger earned 1000 total points
ID: 39852165
Have tracking logs at MXLogic confirmed this message was delivered to your server?

If you use the Message Tracking Logs in Exchange, do they reflect the same error? 550.x.x

Perhaps even check the SMTP Protocol / Connection logs, if you know what time the original message was sent, to see if it was rejected there.
0
 

Author Closing Comment

by:menreeq
ID: 40027645
issue turned out to be on the sending servers end.  Their IT department did not share what the issue they found was.
0
 
LVL 31

Expert Comment

by:Gareth Gudger
ID: 40027712
Glad you got it resolved.
0

Featured Post

Keep up with what's happening at Experts Exchange!

Sign up to receive Decoded, a new monthly digest with product updates, feature release info, continuing education opportunities, and more.

Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

Join & Write a Comment

Are you in the migration process of your Exchange to Exchange Online? Be aware of customized solutions developed on the transport role on your old Exchange server. They might not be convertible to Exchange Online!
Migrating Exchange data from one Exchange Server to another server is complicated. Though Exchange administrators can try manual methods to migrate their data from one version of Exchange to another, these manual methods are not that reliable. That…
To add imagery to an HTML email signature, you have two options available to you. You can either add a logo/image by embedding it directly into the signature or hosting it externally and linking to it. The vast majority of email clients display l…
This video discusses moving either the default database or any database to a new volume.

584 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question