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General discussion

Web shared hosting - Email and IPs getting blacklisted?

Mar 13, 2013 8:37PM PDT

Hi,

I'm on a reseller web hosting package (Apache) on a shared server, and a client has complained that two contacts in the past day have complained to him of getting 'black listed' from our server. In other words, the senders (on third party servers) send him an email and they receive emails back from my server saying that the mail got rejected, 550-"JunkMail rejected". The mail-back also provides a spamcop.net URL for that IP to prove that it is blacklisted (and another contact was blacklisted on mxtoolbox.com). The strange thing is, one of these contacts could mail my client successfully yesterday, but later in the evening (yesterday) he sent a second email and it got rejected.

Is it possible that my shared-server could be reporting these IPs to third party servers, and they reject it? I'm asking my server support too, but I just want a second opinion on what is possible and what I should be aware of in terms of this.

How does an IP go on these blacklists anyway? I'm wary that my own server doesn't do that, but I'm curious if this is possible (e.g. shared hosting servers and generic web hosting providers in the USA - how can I know if they have the ability to report and add IPs to third party black lists?)

Many thanks!

Discussion is locked

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IP
Mar 25, 2013 2:32PM PDT

Actually it is impossible as web hosting will not use a fix IP, and the only reason of your case maybe your client domain has been blacklist, but not the IP.

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Email blacklisting
Apr 26, 2013 1:33AM PDT

Hello Rishijd,

I work with a community support department (we write technical support articles and help our customers generally through our forums) for a hosting company. One thing that has been happening to us is a marked increase in spam email traffic (typically through botnets) that has been affecting our servers. Due to this, security has been increased on the servers to help filter out the spam messages. This has involved both incoming and outgoing messages.

Typically, spam software used to identify messages as spam reviews the content of the email and rates it. When the security increases the factors that would normally state the email is okay change and then identify a message sent later in the day from the same source as spam. So, the email sender IP isn't the issue.

FYI - you can go to SpamCop.net and sign up for an account for free. You can then report spammers and if verified they are added to their blocklist.

One way to stop this from happening is to whitelist your users. You can typically do it in the spam software used by your hosting provider, or you can email them and ask that they whitelist a particular sender as needed.

I hope this helps to provide you the answers you need as well as an avenue that can help you prevent your users from being being blacklisted.

If you have any further questions, please contact technical support available 24 hours a day / 7 days a week.

Regards,

Arnel C.
Community Support

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Thanks
Apr 26, 2013 4:17AM PDT

Thanks for your replies everyone!
Amel, thanks so much for all the details, much appreciated! This helps understand it.

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Very strange
Apr 28, 2013 8:41PM PDT

This problem doesn't usually happen. Strange.