Email on PC using MS Office Outlook is fine but on mobile now an issue

[#1]

Hi all

I wonder if anyone can throw some light on the following....

I use MS Office Outlook on the PC as my email client and the various mailboxes work fine including an external one.  By external I mean a different POP3 domain but using SMTP relay PN.

However, I also use mobile client Bluemail and if on the Wifi at home it all works as well as on the PC. 

Not too sure when I first noticed the problem, possibly a couple of months back (time flies) but when I am out & about and using the PN Mobile data 'link' I found a problem.

I have two of my PN mailboxes and the aforementioned external one on the phone, and they had been absolutely fine when using mobile data connection.  All three then failed to send....a real head scratcher as I was not aware of anything that might have changed.

I checked & rechecked the settings and the error I got indicated it was a server issue (IIRC?) so starting with the two PN mailboxes I found that I needed to change the 'send' settings to secure login = those two mail boxes are fine on the mobile.

But the external one because because it has different POP3 has not 'presence' on the PN system.

Therefore the question is, why does it behave fine on the PC but falls over on the Mobile.  To my inexperienced eye, it is like something changed on the PN email system in that it does not/no longer recognises the Mobile Phones identity.....compared to previously

Many TIA for the insights and a solution.

[#2]

Probably one of three issues...

1. SMTP server configurations do have have authentication set - so they will send when on a Plusnet network (WiFi at home) but will not send when connected to mobile data - relay not permitted
2. When connected to the mobile network, you have acquired a "dirty" (abused) IP address to which Plusnet SMTP relays are refusing connections
3. Your phone is not set to allow the mail application to use mobile data

[#3]

Hi

Thanks for the reply, certainly thoughts to consider.

So , to summarise(as mentioned no issue when on the Wifi but using the email client on the phone):-

1. When I first setup the emails on the phone no SMTP security was needed..whilst using the mobile data/connection..so all worked AOK
   
   
2. When I started troubleshooting the issue
   I found that adding the secure signin for SMTP on the two @Username.plus.comm addresses the send worked AOK
   So the phone does perform when using mobile emails.
   
   
3. But as the external address does not have a 'presence' on the PN email system then there is no SMTP signin to create.
   
   
4. My phone, as mentioned, was 100% AOK using the BlueMail email client.
   
   
5. I have now retested sending an email from the nonPN address to the PN addresses to see the error that I was getting:-
   Error:550 <aaa@username.plus.com> Recipient rejected - Relay denied
   
   
6. As for the 'dirty' IP address using the mobile....I use PN Mobile. So is it rejecting "its" own IP source?
   If the reason for the problem is such a 'dirty' IP, why is that happening?

TIA for your extra insights

[#4]

Responses...

1. If you were using the MOBILE data connection SMTP authentication (not to be confused with encryption) WILL most certainly have been required - it is simply NOT POSSIBLE to access the SMTP server without authentication when not connected to the Plusnet network
2. Secure sign-in is AUTHENTICATION plus ENCRYPTION - for SMTP that should be port 587 with STARTTLS
3. Do not understand your terminology
4.  - OK
5. Very much proves that the SMTP connection configuration is has no AUTHNTICATION details what so ever - if that were configured and was wrong you would get a logon failure - "relay not permitted" is a clear indication that no log on for the SMTP server was attempted
6. Dirty IP addresses (in whatever environment) arise from abuse by some previous user - Plusnet do not have their own mobile network, they use EE's, so there is no sense of they rejecting connections "from their 'own' IP source" - FWIW if one of their own network IP addresses has been abused, it could well face the same quarantine, often seen as "too many failed log in attempts from this IP address"

Go back to the basics and check the SMTP server settings in your email clients...

• Server: relay.plus.net
• Port: 587
• Encryption: STARTTLS (note some clients do not list this option, but might use SSL and work through the variations - certainly iOS mail does this)
• Authentication: Use the same as the incoming server

[#5]

But as the external address does not have a 'presence' on the PN email system then there is no SMTP signin to create.

If you are sending via the plusnet servers, then you will still need to authenticate using your plusnet credentials. However, that's going to be the least if your problems, sending  using an external email address is almost certainly going to fail to Gmail.com  addresses due to lack of SPF

[#6]

Thanks again for the insights...

I will re-review the settings and look at what might be possible?

But the thing that still bugs me is that up until I found the problem the SMTP (send) for the none PN address worked without signin/authentication ~ so as say/infer it should not have worked but is did.....as it does when on the WiFi

Perhaps up until that point it sort of "slipped through".

I may have to look at alternate solution(s)?

I will as you say go back to basics and check my settings again

[#7]

Thanks for the reply.

The none PN address in question is not a Gmail (or any other general one) but associated with my website domain.

[#8]

THEY might permit (or might have) open relay, Plusnet does not.

This forum is for the support of Plusnet’s email services. Does your web hosting provider provide a support environment for issues with their services?

[#9]

I understand what you are saying.....

But to repeat myself:-

When setup the email on my phone for use (including when off of WiFi) it worked AOK for both the two PN addresses I use and the none PN address.

In none of the above was SMTP signin required (Open relay???)

Latterly (the reason for starting the thread) I the issue and found that I had to add the signin for the SMTP for the PN addresses and that worked but the non PN address failed for what are obvious reasons i.e. SMTP relay authentication is not possible.

The overarching question (in part applies to the PN email addresses......why did it originally work for a good while (current phone and the previous one) and then fail(?) requiring the authentication.  In other words, why the change?