Mailchimp newsletters being refused by btinternet

[14Steve14]

For the past 12 years as a business we have been sending a weekly newsletter to our customers via Mailchimp. We had no problems with emails bouncing or being rejected by mail servers until recently. Now for some reason btinternet email addresses are bounced back to Mailchimp. We have gone from one or two bounces a week to nearly 300 a week now, all being btinternet email addresses.

To the best of our knowledge Mailchimp have changed nothing but its hard to contact them as we are on their free plan, so no support. I am a btinternet customer and have had no problems but the sending email address is in my safe senders list. If I take the sending address out of the safe senders list my weekly newsletters bounce. 

There is no reason given for the bounce, but can only assume that BT has made some setting change. I dont believe the error is with Mailchimp because all the other emails set are received.

I have done a quick search of this community and cannot find a similar problem. Does anyone have any idea why these emails are being bounced by BT internet.

[rbz5416]

I'm not on the same scale but have 247 addresses in my Mailchimp Audience, of which 20 have @btinternet.com addresses. I've just checked the three emails I've sent this month & none have bounced, although the last one was sent on 12th.

[14Steve14]

Thanks for the reply. We have about 500 BT email addresses in our list and like I say over 300 are getting bounced back. I suppose the good news is that at least some of them are getting through, but that's no consolation to those that don't get one. We have about 25 of those who are not receiving these weekly newsletters contact BT email support and so far not one of them has had a reply.

Why BT don't mark the email as spam and deliver it to their spam folder I have no idea, but that seems to be an ongoing recent complaint about BT which has been posted in these groups.

We are currently trying to convince then to add a different email address so they can at least read them.