550 4.4.7 QUEUE.Expired; message expired


EQ Forum Admin
Staff member

Is your Microsoft Exchange server having trouble relaying or smarthosting and generating the following error?

550 4.4.7 QUEUE.Expired; message expired

First, please check it's network connection, DNS settings, and that you have outbound port 25 access to the internet.

Then check your mail logs and determine if the problem affects all outgoing email or only email to some domains.

If the problem is only sending to some domains make sure that your server is not being used for spam, whether is be compromised accounts being used to spam, relaying for another server or user that's spamming, and that it's not a source of backscatter.

If you find a spam/abuse problem fix the source of the issue and then check to make sure that you are not on any blacklists.

Monitor your mail logs or use a tool such as mxtoolbox.com to check for blacklistings.

If you would prefer to smarthost your outgoing email through a 3rd party smarthosting service we recommend LuxSci Smarthosting.
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