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ip address blacklist

kevin_373
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I'm having problems sending emails from my mobile. Upon investigation it seems to be down to the IP addresses assigned being blacklisted. I looked at the last 6 IP addresses and 3 are classified as "High Risk" and 3 as "Suspicious". All are identified as being Telefonica, Edinburgh. I am using the installed email app on my Samsun Galaxy. When I set up a mobile hotspot to connect to my laptop I experience the same problem with Outlook in that I cannot send emails but I can receive them. I've looked back at previous postings and can see this same issue occured over 10 years ago  - hoping that there has been a fix in the interim 😉

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O2Emma
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@MI5 I agree its a workaround whilst o2 can look into issue with the ip addresses for the emails not being able to send from the inbuilt mail apps on the phones. I know it has been a on/off issue for awhile and I will try and get more info regarding it to be able to let you know.

 

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MI5
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Thanks @O2Emma 

Appreciate the help.

I have no affiliation whatsoever with O2 or any subsidiary companies. Comments posted are entirely of my own opinion. This is not Customer Service so we are unable to help with account specific issues.

Currently using:
Pixel 7a (O2 & Lyca), One Plus 6 (Sfr), iPhone 12 Pro Max (Vodafone)
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O2Emma
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No problem @MI5 .

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David_Parr
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My email provider, 123-reg, told me today that there were at least four O2 IP addresses associated with my emails alone that are marked as unsafe. They seem to think that it is just a matter of O2 contacting the blacklist people to request they remove these IP addresses.

 

I would have thought that someone who is as well known and important as O2 would be removed from the blacklist on request. Five minutes work to look after the simple needs of lots of customers is a no-brainer for O2 surely?

 

At the moment, anyone with a gmail address I send an email to, I have to follow up with a text to tell them to remove it from their SPAM folder. It's a bit annoying!!!

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bunzena
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Hi - just to add to this - having been alerted to by MI5 after posting a question on the forum about emails not making it through.

 

After a week of sending emails to clients - and then discovering that some have not been received - looks like it's a O2 IP blacklistiing issue.  It's been a problem of nightmarish proportions for us. 

 

We're dealing with senior people at clients like Coke and AXA.  Trying to work from home during lockdown. Can't talk directly to anyone at O2...it goes on.

 

ANYTHING you can do or chase up - we'd be very grateful for.

 

And it would be helpful if someone at O2 would communicate more widely that this is a known issue.  It's taken us a fair few days to get here.

 

 

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madasaf1sh
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@bunzena

 

Apologies only just seen this thread.

 

What is the NDR / DSN message that you get back from the mail server, as this will tell you exactly what the error is.

 

Most ISP's are on one or other Blacklist and this includes, BT, Virgin, AAISP etc

 

The only time o2 will be blocked is the original connection to the Email Gateway / Mail Service, so SpamHaus and other RBL's will only report IP's that are used as Open Relay's or for Spamming purposes by someone building a Mail Server and using them. 

 

When you connect via Outlook you connect to your corporate mailserver, and all mail is routed through this your o2 IP address will only show as the Originating IP Address (x-originating-ip) 


If you use Gmail then it doesnt even send a x-originating-ip, when sending mail out from outlook ior

The Subnet 82.132.236.0/22 doesn't exist in the SpamHaus Drop List which is what peers use to drop / reroute connections.  


I have also checked that Subnet on various Mail Gateways (O365, My own Mail Server and GSuite) and that IP isnt blocked. 

 

The more i think about this the more, it sound like what I experience with one of my webhosts and from a professional capacity  is that when the firewalls (or mail gateways) see a large number of connections from single IP address (bareing in mind o2 connections and most ISP's / Corporates use a single (or multiple) internet break outs as your IP is nat'd) they will block those connections or filter them out and re route them out to a DMZ and then drop them. 

 

It might be worth asking your Corporate IT Team to put a network trace on a connection from your machine's IP in to the mail server and seeing where the traffic is being blocked. 


They / You can also reach out to the Webhost and ask them to check the Firewall for connections being dropped. 

 

If you need any help, happy to check MailHeaders etc ( i manage mailservices for a living, for my sins).

 

@MI5  if you are getting incorrect username and password on o2, then depending on your mail service, it will be down to a possible connection block on your corporate firewall (assuming its your corporate email service). 

 

 

 

edited as clicked post too early

- Xperia 1V - o2 and Spusu
- Pixel 8 Pro - o2 and Vodafone UK
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O2Emma
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Update @MI5 I have been asked to gather examples of the issue so if any of our community ask about this email ip address or spam issue please can you direct them to this post so I can private message them to get the information needed to continue looking into it.

 

Thanks grin

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O2Emma
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Hi @bunzena I am going to private message you so i can get some details of issue as we are investigating it at the moment.

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David_Parr
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My current, blacklisted, O2 IP Address is 82.132.245.157

 

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David_Parr
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My email is still bouncing to some email addresses. O2 simply do not care.

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