Why does email bounce?

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The following message to was undeliverable.
The reason for the problem:
5.1.0 - Unknown address error 550-'5.1.1 : Recipient address rejected: User unknown in relay recipient table'
Does this message mean that my email is being blocked by this person. Is there a way to see if someone is blocking your emails.
PS I removed the persons email from the message.

Has nothing to do with a person blocking you - there's no way to know if a person is blocking you. This error typically results from either a misconfigured mail server (which may resolve itself, or not), or typing in the email address wrong.

06-Aug-2009

Hi,
I have an mail application develeped by ASP.NET. IT works fine for different domains, but it displays error as
'Mailbox unavailable. The server response was: Requested action not taken: mailbox unavailable or not local' for same domain.
My files hosted in Windows server and mail server is Linux..

Hi, I am getting the error message - This address no longer accepts mail. Can you help please?

Thanks in advance

No, I cannot. The error message pretty much says it all. I'm not sure what you'd expect could be done.

25-Aug-2009

How do I resolve this problem?

Remote host said: 550 SC-001 Mail rejected by Windows Live Hotmail for policy reasons. Reasons for rejection may be related to content with spam-like characteristics or IP/domain reputation problems. If you are not an email/network admin please contact your E-mail/Internet Service Provider for help. Email/network admins, please visit http://postmaster.live.com for email delivery information and support

Mine bounces but says it is a permanent error
that my e/m is blocked by Verizon anti- spam
system. I am convinced this person has blocked me?

I lost a job opportunity when I could not respond to the job offer within the set time because my ISP, Comcast, was blacklisted for SPAM by Blackhole. I tried every one of my Comcast addresses, my Hotmail and G-mail addresses and all got bounced. When I contacted the blocking agency they told me sorry, there was nothing they could do for me. I called Comcast and they said, "We're working on it." Meanwhile, I didn't get the job. Another time a friend from upstate New York, almost in Canada, sent me a joke with the word Viagra in it. It was a good joke so I replied to tell him so and had some other chit-chat to tell him. I was both bounced and blocked and later found I had been permanently blocked and labeled as a spammer because of the word Viagra in the email and because my reply included his original email. He used an animated emoticon in all his emails and the emoticon had a link at the bottom of the email page for recipients to click on to get free emoticons, too. I had to call his ISP via phone and plead my case to be unblocked. It was a huge hassle and if he wasn't such a good friend I would have given up. Again, any email from my computer from and email service was blocked. I had another unpleasant experience with another friend whose ISP had installed software called Barracuda to filter SPAM and it was still in learn mode when I got repeated bounces when I tried to email him. It bounced me for everything from keywords to having multiple "To" addresses with maddening frequency. I complained to the ISP probably a dozen and a half times before it stopped. I even emailed the makers of Barracuda and complained. of course, I never heard back from them. Hopefully the company folded.

Hi,

I am sending emails from my own web server, but some emails are getting bounced. So do you know any solution which will give me a count of bounced emails??

Your help will be appreciated.

Thanks,

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