Emails to gmail addresses via "relay plus.net" are either rejected as spam or disappear

[#1]

Emails to gmail addresses via "relay plus.net" are either rejected as spam or disappear
Since migrating to Plusnet's full fibre emails sent via "relay plus.net" to gmail addresses do not arrive, including ones to my own gmail address.
For instance, emails received to my Windows PC from Amazon via "mail.plus.net" (TCP/IP port 587) which I want to forward unedited to my gmail address (to be accessed on my phone) are rejected as "552 FyO###############R04 message rejected due to spam or virus".
Other emails sent via Plusnet, addressed to my gmail account, with 'Subject' "Test", with only the word "Test" in the body, simply diappear,
I have looked through https://community.plus.net/t5/Email/Emails-to-gmail-randomly-disappearing/td-p/1924440 but saw/understood nothing that helped there.
Plusnet's 'Safeguard' and firewall are swiched off.

[#2]

This sounds odd, so there must be some overlooked detail or confusion.

For receiving emails from mail.plus.net a POP3 client would use port 995 with TLS/SSL encryption, not 587.

For receiving as an IMAP client it would be imap.plus.net using port 993 with TLS/SSL.

You do not though seem to have an issue receiving so your description must simply be a confusion of receiving and sending server configuration details - POP3 incoming server referencing outgoing server’s port number.

Did this all work as is before changing to FTTP (from some other connection provided by Plusnet)?

Are you certain that there have been no changes made?

Is the outbound server connection (to relay.plus.net port 587 with STARTTLS) set to require a logon?

Are you sending from you@account.plus.com ?

If you want your Plusnet email mail to be received on your phone, you could make life simpler and just add your Plusnet email address to your phone’s email application.

[#3]

@Townman , I think you have misunderstood the OP's problem.

I believe it is that emails sent from the OP's Plusnet mail address to any gmail address are being rejected as spam, not that all emails are being rejected by Plusnet. This has happened before for other Plusnet users. Sometimes it is transient. Sometimes a change of IP address helps.

Using a different e-mail provider also works.

[#4]

@corringham 

I think I understood correctly, in the manner you cite, however the detail of the OP is either confused or potentially points to a configuration issue.  Whatever the scenario seems very odd if there has been no change in the configuration client doing the forwarding.

If this is ONLY being seen on forwarding AMAZON emails, then that points to Gmail having an issue with the content of the AMAZON email - possibly a false positive - and probably has nothing to do with the wholesale rejection of emails sent via Plusnet's servers as discussed elsewhere.  SPAM filtering profiles evolve over time - sometimes such changes can be coincident with other changes, leading to one drawing the wrong conclusions.

One way to discern that is to prepare to forward the email and then chop bits (particularly links) out until it arrives without issue.  Also try forwarding the email as an attachment.

The key points remains though...

1. Has anything else been changed since the switch of connection services (other than the allocated IP address ... which could be the actual issue)
2. What email address is the user using for the sent email address
3. If the only reason for forwarding to Gmail to see the emails on their phone, configuring the Plusnet account on their phone is a much simpler solution
4. New idea: similarly if the user has no real need for the mail to be in the Plusnet space at all, then a far simpler solution still is to delete the Plusnet mailbox and then forward the address to Gmail

[#5]

Hello

Thank you for the quick and detailed reply.

[I use Pegasus email client (for 20+ years), which coincidentally has just developed a new glitch which means it retrieves emails if I reboot the PC, but for no apparent reason after it's been running an indeterminate length of time, it won't. I'm still investigating that.]

POP3 had been set to port 110, not 995. No TLS/SSL encryption. I tried using 995, no response. Port 110 works ok.

Outbound server connection is to relay.plus.net port 587, no STARTTLS, no logon.

Not sure what "sending from you@account.plus.com". Afaik, there's a logon for receiving mails, but not for sending.

Afaik, until we went full fibre, I had no issue sending to gmail.

I agree about using an email client on my phone, but as far as I can see, Pegasus is the only email prog that allows selective download: I want to choose which emails to retrieve and which to delete from the server.

[#6]

Thanks for the quick reply.

Could you elaborate on what a "change of IP address" would entail? I have a static IP address with Plusnet: is that what you mean? Changing that would be awkward.

Also on "using a different e-mail provider"? I can use Yahoo, but it would be much simpler to use Plusnet's already paid-for service/

Thanks again for taking an interest.

[#7]

Hello again,

Thanks for persisting!

I thought that about Amazon's mails 'false positives' possibility, but it seems any email sent to a gmail address just disappears. Including ones with a simgle work subject line, and a single word message, "Test".

I have a static IP address through Plusnet, which did not change on going full fibre.

My 'sent email address' has remained the same for years: it uses my own domain name.

Not sure what you mean by "delete the Plusnet mailbox and then forward the address to Gmail".

I suspect I could be chasing my tail looking for a solution to this issue, when it looks to me like it's a Plusnet email server issue. I think I'll try to deal with Plusnet directly.

Thanks again.

[#8]

My 'sent email address' has remained the same for years: it uses my own domain name.

@Philbert and that is likely the problem!  Does your domain have an SPF record which defines the Plusnet servers as  authorised senders ?

Gmail introduced a requirement that mail to gmail addresses must have SPF and/or DKIM authentication

[#9]

Thanks for the reply.

"Gmail introduced a requirement that mail to gmail addresses must have SPF and/or DKIM authentication"?

Interesting!

I shall investigate the SPF record thing.

Cheers,

H

[#10]

@Philbert is your domain hosted by Plusnet ?