Bcc emails rejected as spam

I run a small natural history group with about 70 members. It's become almost impossible for me to email the group using the blind copy setting because most email servers are rejecting my message as spam. Messages used to end up in the spam folder of many recipients but at least I could warn them to check their spam folder. Data protection means I can't send messages without using the bcc setting so I'm either going to have to email every member separately or go back to putting letters in an envelope and posting them! Is there something else I can do?

RolandJS said:

What about creating and sending three groups bcc? 25, 25, 25. As you add more members, they simply become part of a fourth group.

Thanks for the suggestion but I've just tried sending a message to just 4 recipients and 3 were rejected and one went to a spam folder so it isn't the quantity in the bcc field that matters.

idgat said:

More likely an over-zealous ISP, either yours or theirs.

Might be worthwhile looking at a non-ISP based service - get a Gmail account (and use a mail client like eMClient or Thunderbird), or use a service like MailChimp

I've done both and seems to have solved my similar problems for my social group, particularly the MailChimp option. Free service with limited "members" (they call it an "audience" - mine are 84)

Thanks for the suggestion. I've just signed up with MailChimp and added contacts. It's aimed at businesses of course but free for upto 500 contacts so ideal for me. I haven't worked out how to send emails yet though...

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idgat said:

I suspect your IP address has been (maybe only temporarily?) flagged as a source of spam, again by either your or their ISP.

I'm using mail.com as my email service so I'm not sure how that affects things. Here is a sample of rejected email messages (with the recipient addresses deleted)

Email address 1
SMTP error from remote server for MAIL FROM command, host: outlook-com.olc.protection.outlook.com (104.47.17.161) reason: 550 5.7.1 Service unavailable, Client host [82.165.159.131] blocked using
Spamhaus. To request removal from this list see https://www.spamhaus.o
rg/query/ip/82.165.159.131 (AS3130). [VI1EUR05FT058.eop-eur05.prod.pro
tection.outlook.com]

Email address 2
SMTP error from remote server for RCPT TO command, host: mail3.eqx.gridhost.co.uk (95.142.156.6) reason: 550 Administrative prohibition

Email address 3
SMTP error from remote server for RCPT TO command, host: mail3.eqx.gridhost.co.uk (95.142.156.6) reason: 550 Administrative prohibition

Email address 4
SMTP error from remote server for TEXT command, host: mx3.ex.ac.uk (144.173.6.33) reason: 550 This message appears to be spam (score: 5.2)