Outbound emails not being delivered - perhaps being marked as 'SPAM'

[bunzena]

Hi - need some help and advice on a problem that's proving hard to solve.

Have been sending emails from an iPhone and a PC [using Outlook 2016] via mobile broadband.  Use a data SIM.  A number of those emails [some to clients] are not being delivered. 

There's no clear pattern to those that are and aren't delivered.  Failed delivery could be to addresses at a commercial/business domain - or it could be **Personal info**.

The best explanation I can find is that the O2 IP is being flagged on a blacklist as a generator of SPAM.  Using Spamhaus and feeding in the O2 IP - shows it up as 'flagged' on a number of blacklists.

If I reboot the phone [or the router] and get a new IP asigned - this inevitably has the same problem.

All the IPs I've had asigned are in the 82.13.XXX.XXX range.

We've checked ALL our settings and all of the tech - but no joy.  We've had long convesrations with our domain host about whether it's an issue at their end - and they've investigated extensively.

In comparison - if I send the same email to the same address using BT Broadband - the email gets through.  

Frankly it's driving me completely nuts.  Any thoughts?  Anyone else had the same issues?

[MI5]

@bunzena 

It's a known issue that has been reported already.

@O2Emma is looking into it for us.

[bunzena]

Thanks - really good to know!

Sorry - didn't spot this had already been picked up on the forums.

[MI5]

No worries @bunzena 

Keep your eye on this thread https://community.o2.co.uk/t5/My-O2/ip-address-blacklist/td-p/1409395

[O2Emma]

Hi @MI5 

@bunzena please keep a eye on other thread as soon as I get any information I will post it 

In the mean-time if you can use your email providers app.