Invalid recipient on when sending

Posted on 2007-11-15
Last Modified: 2008-02-01
I try to send an email to, using one of my email accounts I get it bounced back instantly with an "invalid recipient" message.
The mail server is, if I try any other of my email accounts with different isp's it works fine.
Why might this be happening?
Thanks for any help.
Question by:RickJ
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 5
  • 3
LVL 16

Expert Comment

ID: 20294720
It may be that the ISP for the account you are trying to send email from is blocking ".biz" tlds (top level doman names)

.biz domains are frequently used by spammers and as a consequence get blocked for both outgoing and incoming mail.

Author Comment

ID: 20294734
Hello thanks for the quick reply,
How would I verify that is happening without contacting the ISP?
LVL 16

Expert Comment

ID: 20294838
If you have another ".biz" email address try sending an email to that address - if it goes through then your ISP is not blocking .biz domains.

However, the best solution is to ask your ISP.

By the way what is the exact bounce message you receive?
Increase Agility with Enabled Toolchains

Connect your existing build, deployment, management, monitoring, and collaboration platforms. From Puppet to Chef, HipChat to Slack, ServiceNow to JIRA, Splunk to New Relic and beyond, hand off data between systems to engage the right people.

Connect with xMatters.


Author Comment

ID: 20294908
Thanks I will try another .biz address.
The error is as follows;

Your message did not reach some or all of the intended recipients.

      Subject:      test email
      Sent:      15/11/2007 8:09 PM

The following recipient(s) cannot be reached:

      '' on 15/11/2007 8:09 PM
            550 Invalid recipient: <>

Author Comment

ID: 20295323
I tried another couple of .biz and they sent successfully.
Do you still think this is likely to be an ISP problem?
LVL 16

Accepted Solution

grahamnonweiler earned 500 total points
ID: 20298142
I have myself just tried to send an email to "" and got 2 errors - the first was a graylisting command from the ATLANTIC SMTP server (the host mail server for which is normal and nothing to worry about, the second was a 550 error saying the account  "" does not exist.

So it seems the error is with "" and not your ISP.

If you have another way to contact "" then you should tell them that their email is returning "transient" sending errors - it could be that they have some capacity limits or other issues with their host.


Author Comment

ID: 20306548
Thanks for that.
I am now trying to deal with the hosting company to rectify the problem, like drawing blood from a stone...
Thanks again for your help.

Author Comment

ID: 20324605
Hello again,
Wondering if you could please help me out.
The hosting company is asking for another mail server that is not that cant send to this address.
You mentioned that you tried and it wouldnt work, are you able to tell me the server you are using to send?

Thanks again for your help.

Featured Post

Get 15 Days FREE Full-Featured Trial

Benefit from a mission critical IT monitoring with Monitis Premium or get it FREE for your entry level monitoring needs.
-Over 200,000 users
-More than 300,000 websites monitored
-Used in 197 countries
-Recommended by 98% of users

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Workplace bullying has increased with the use of email and social media. Retain evidence of this with email archiving to protect your employees.
Marketers need statistics and metrics like everybody else needs oxygen. In this article we explain how to enable marketing campaign statistics for Microsoft Exchange mail.
In this video we show how to create a Resource Mailbox in Exchange 2013. We show this process by using the Exchange Admin Center. Log into Exchange Admin Center.: Navigate to the Recipients >> Resources tab.: "Recipients" is our default selection …
The basic steps you have just learned will be implemented in this video. The basic steps are shown to configure an Exchange DAG in a live working Exchange Server Environment and manage the same (Exchange Server 2010 Software is used in a Windows Ser…

689 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