‘550 no rDNS entry for xxx.xxx.xxx.xxx’ means that there is no reverse DNS record for the sending email server.
You may see this error in logs :
Tue 2018-09-04 10:36:46: <-- 550-Sending server has no reverse DNS (PTR record)
Or you may get a bounce back message :
firstname.lastname@example.org>: host mail.[destination_ip] said: 550 No rDNS entry for 100.200.300.400 (in reply to RCPT TO command)
554 5.4.0‘ is a email bounce error that is usually seen after a server migration or a mail server reconfiguration.
Here at Bobcares.com, we help hosting providers (web hosts, VPS hosts, etc.) resolve such errors as part of our Outsourced Tech Support services.
A typical email bounce looks like this:
host xxx.xxx.xxx.xxx[yyy.yyy.yyy.yyy] said: 554 5.4.0 id=03742-03-6 - Rejected by next-hop MTA on relaying, from MTA(smtp:[zzz.zzz.zzz.zzzz]:31142): 554 5.4.0 Error: too many hops (in reply to end of DATA command)
cPanel/WHM is the most commonly used control panel in hosting industry. In our role as outsourced hosting support specialists for web hosting companies, we resolve many errors related to the control panels.
Using the WHM, it is easy manage various services in the server, but there are many situations where these features fail or give errors, and expert intervention is required. (more…)
SMTP error from remote mail server after RCPT TO:<email@example.com>:
host mx.server.com [xxx.xxx.xxx.xxx]: 550-Verification failed for <firstname.lastname@example.org>
550-No Such User Here
550 Sender verify failed
Bobcares provides website management services to website owners. Email errors are the most commonly encountered issues by the end customers.
Amongst these mail errors, ‘Sender verify failed’ is a prominent error that creates so much hassle to account owners. We’ve seen that it can be caused by issues ranging from improper file permissions to RFC non-compliance. (more…)
Emails play a crucial role in online communication. Business orders to meeting invites, lost or delayed mails can end up creating disgruntled customers.
In our role as Website Support Specialists for online businesses, we resolve hundreds of mail issues every day. A commonly encountered email bounce error faced by web hosts, website owners and server owners is:
554 5.7.1 <email@example.com>: Relay access denied (more…)
In our role as Website Support specialists for web hosting companies, we’ve seen internet users sending emails to certain recipients encountering the error:
550 5.1.1 <firstname.lastname@example.org>: Recipient address rejected
This error is associated with recipients whose emails are hosted in Exchange and Postfix servers. Today we’ll discuss the reasons for ‘550 5.1.1’ error and how to fix it. (more…)
A commonly noted error in Microsoft Exchange 2007 server is when the emails from certain 3rd party applications or scripts fail to deliver.
The mails get rejected, giving this error message in the logs:
SMTP MAIL command failed Error (501) 5.1.7 Invalid address