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jt_dt
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SMTP whitelist rdns as9143

Hello,

When our web application tries to send emails to virginmedia.com, blueyonder.co.uk and ntlworld.com email addresses.  They are refused.  Error is a mismatch in entries for RDNS, difficult to resolve at this end.  From logs....

2020-12-14 09:10:19 212.54.56.11 OutboundConnectionResponse SMTPSVC1 PREWA1 - 25 - - 421+EHLO+MXIN201+Your+HELO/EHLO+MTA4.distribution-technology.com+is+not+matching+your+DNS+configuration+dt-mta5.uksouth.cloudapp.azure.com+;id=ojs3kuHpPj78H;sid=ojs3kuHpPj78H;mta=mx7.tb;d=20201214;t=101019[CET];ipsrc=20.49.227.202; 0 231 0 78 SMTP - - - -

I tied emailing the postmaster address a few days ago.  No response.  I tried calling customer support as Virgin's customers are complaining to us that they cannot receive emails from this address, so hopefully someone watching the forum can send this query in direction of your internet security team as has been done in the past for other users (I really don't like airing my washing in public).

Our dns is not hosted within Azure so we cannot use distribution-technolgy namespace.  RDNS checks don't like alias', so I don't think that is an option.  Due to nature of firewall one of two static IP addresses can be used.  Neither are shared with any other organisation, neither are on any publically accessable blacklist.

If someone from support is willing to help I can supply 2 IP addresses that need whitelisting to bypass your rule.

Many Thanks,

James

pierslawson
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Re: SMTP whitelist rdns as9143

I was told by my adviser that this was the reason for his emails not getting through to me. Please can this be sorted quickly!

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Megan_L
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Re: SMTP whitelist rdns as9143

Hi Jt_dt, 

Thanks for using the forums to get this issue with your Email looked into, I am sorry if this has been causing some frustration. 

I have emailed your issue over to the internet security team who will look into this for me, and hopefully give us some further help and advice on how we can get this resolved for you. I will update you with any further info I get.

Sorry if this has been causing some inconvenience.

Thanks,

Megan_L 

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Megan_L
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Re: SMTP whitelist rdns as9143

Hi Jt_dt,

The team have got back to me with a couple of questions for you, they may not be suitable to ask over a public space so I will send you a PM now so we an chat privately. 

Speak soon!

Thanks,

Megan_L

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Megan_L
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Re: SMTP whitelist rdns as9143

Hi Jt_dt,

Thanks for giving me an update in our PM, I'm glad this issue was resolved with the help of our Internet Security team 🙂

If you need any further help with this in future please let us know so we can chase it again.

I hope you have a very Merry Christmas and happy New Year!

Warmest regards,

Megan_L

 

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jt_dt
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Re: SMTP whitelist rdns as9143

Hi Support,

This issue has come back again. Is it possible to get us added back onto the whitelist?

Many Thanks,

James

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Emily_G
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Re: SMTP whitelist rdns as9143

Thanks for the update, is it exactly the same as previously or are there any changes if you check the things we went through with you previously? 

 

Thanks, Emily.

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jt_dt
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Re: SMTP whitelist rdns as9143

Hi Emily,

Thanks for getting back to me.  Error is the same as last time.  Nothing has changed at our end.

Many Thanks,

James

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Emily_G
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Re: SMTP whitelist rdns as9143

No problem, I'll forward it on to Meg who was looking into this previously so she can hopefully just follow up on the previous emails with the team to get this looked into. 

 

Thanks, Emily.

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jt_dt
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Re: SMTP whitelist rdns as9143

Thanks Emily, I await to read her response.
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