Mac OS 11.6 Big Sur, Mail app: cannot send emails with attachments (photographs or video mp4 files)

[#1]

Plusnet used to provide my broadband and mobile carrier but I am now with EE. Plusnet has allowed me to retain my Plusnet email address. Everything has worked perfectly but I am now experiencing problems sending emails with either photographs or video (mp4) files. I regularly send on emails to a group of 11 contacts. I now receive  a message from my Mail app "Cannot send message using the server (my email address) - The server "relay.plus.net" did not recognise the following recipients... The server response was: Too many rcpts from this IP. I'm then invited to select a different mail server from the list below or click 'Try Later' to leave the message in your outbox until it can be sent. The system keeps trying to send the email but fails.

I have checked all my settings and re inputted my password but the problem persists. Very frustrating. I have no problem with word only emails.

Any assistance would be appreciated. Thank you.

[#2]

Hello @keithatmoleend

It's not an issue with your email settings, it's a problem that we've seen raised a few times as of late, likely an issue on our side.

My colleague has raised this matter and we're just waiting on a response as to what's being done about it.. Please bare with us for the time being and if possible, send your emails from any other accounts that you might have,

[#3]

The situation is becoming worse. I now cannot send a simple one line email to a recipient, but I continue to receive emails from all sources.  It is the sending that is failing.

[#4]

Thanks for getting back to us @keithatmoleend

Are you getting the same error? Also could you try sending from webmail.plus.net?

[#5]

I have now upgraded to Mac 12.01 (Monterey). The issues remain. I deleted my principle Plusnet account in the Mail Application of Mac OS 12.01 then reinstalled it.  I have succeeded in sending a jpg file to myself using the Mail App with Mac OS 12.01. A  message addressed to my group of 14 contacts will not go. I receive a message from Mail to say:"Cannot send message using server ............plus.com. It then lists a number of my contacts The server "relay.plus.net" did not recognise the following recipients (five email addresses shown). The message continues: The server response was: Too many rcpts in time period from this IP. The message then invites me to select a different outgoing mail server from the list below or click Try later to have the message in your outbox until it can be sent.

I have now also enabled Plusnet Webmail. I can send a jpg file to my self using webmail. However if I try to send the same jpg file to my 14 contacts I receive the following message: SMTP Error [451] gjBTmVSntRbo9gjBumEgZ5 max recipients breached.

Until this last week I have had no problem with my Plusnet email using Mail within Mac OS. It appears there is a fault with "relay.plus.net" or there has been a change of policy. It is most frustrating.

Thank you.

[#6]

@keithatmoleend Does this help you in any way?  I am using Monterey v12.01 and I can send email using these settings. Granted there's a delay in their receipt of about 4 minutes but it still works for me.

[#7]

Thank you. I see that your email account is an IMAP account rather than a POP account. I do not have the technical know how to appreciate the difference. However I have deleted my Plusnet POP email account and created an IMAP account. The issues remain.

After more research I think I may have found the crux of the matter. My broadband supplier is EE, not Plusnet.It may be the case in my email settings I need to input some form of authentification on my SMTP but I cannot bring up the relevant page within my Mail settings.

Would appreciate any suggestions.

[#8]

Thank you. Plusnet webmail will not send an email with a jpg attachment to multiple recipients (maximum number breached).

Please see my earlier post to Mook. My broadband supplier is EE, not Plusnet. I feel my SMTP settings may need some form of authentification but if that is the case I am at a loss at the moment on how to do so.I have seen screen shots of settings within Mail on Mac OS that I do not seem able to create.

[#9]

Thanks for getting back to us @keithatmoleend

I don't believe the issue lies with your email settings at all, as Adam's said it seems to be something our end based on how many people are reporting a problem. We should hopefully know more on this next week.

[#10]

OK, thank you. In the meantime can you please clarify whether my Plusnet email account within Mail (Mac OS) should be a POP or IMAP account and what difference does it mean?

[#11]

Thanks for getting back to me @keithatmoleend

No problem, it can be either. We explain the differences between POP3 and IMAP Here.

"IMAP

1. Emails stay on the Plusnet system even after you've checked them on your computer
2. Whatever you do with your emails happens on all the email applications and devices you're using
3. You'll need to be connected to the Internet whenever you want to check your emails
4. Best if you're using different devices for your emails, like an iPad or smartphone

POP

1. Emails stay on the Plusnet system until you check them on your computer
2. Then your emails move from the Plusnet system to your computer
3. They won't be on the Plusnet system anymore
4. Your emails stay on your computer so you can read them even if you aren't connected to the Internet"

Let me know if you need any further help. 

[#12]

Well, well, fingers crossed it appears that whatever was the problem has been fixed, (hopefully) 😃.  I have been able to send two separate emails to multiple recipients from the Mail application in Mac OS. Each email contained either a jpg file or mp4 file.

I am a happy bunny and very relieved.

Thank you everyone.

[#13]

Cheers for the post back @keithatmoleend 

I’m glad to see this is sorted for you now and you’re able to send emails normally again 

We found an issue our side and we fixed it.

Let us know if you have further issues or there’s anything else you’d need help with.