Some of the techniques are patently dumb.
I once tested, with a friend of ~15 years, sending a 1 word email to his gmail account. It was always dumped. Making it 2 words made it go through. That is dumb and that is google! The doubly dumb thing is that this guy sent me maybe 1000 emails (via his gmail webmail account) and nobody is going to send any significant number of emails to a spammer, so not whitelisting a sender who you send emails to is incredibly dumb. And in this case, as I said, 100% loss for English text and a 0% loss for French text. So I am not doubting that multiple methods are used but you need to implement only one really dumb one (like not whitelisting senders who you send emails to, or dumping all non-French emails) and it all falls over.
Imagine being a French company which is trying to export and uses one of these ISPs.
I had a professional spammer commercial bulk mailer live across the road from me and his pub stories were quite funny, but he had to spam a million at a time, at a high speed, so had to work with the major ISPs to arrange acceptance.
autorouter also has issues with message returned by @free.fr addresses. Seems like a poor email service.
Peter wrote:
notably free.fr
free.fr is a pain in the a**. They reject my e-mails from yahoo.no.
This has started again with free.fr
Those here with .fr email addresses are probably not going to receive forum PMs which are in English.
It is happening again.
Not a lot you can do other than to avoid using free.fr if you want to communicate with countries outside France.
They seem to be letting in DKIM signed emails (I use DKIM for the mailings re fly-ins and have not had the en-masse bouncebacks we used to get) but forum notifications don’t use DKIM because there is a much higher volume of these and it costs money.
You can set up SPF, DKIM and DMARK on any host you own for free, it doesn’t cost a dime.
As long as your IP is not blacklisted somewhere, it will work just fine. Check here:
Spam is a hassle, that’s for sure. Dimme is right, what’s needed is not linked to the number of mails you send – it just requires config.
I have customers that need to send email invoices to millions of their customers, and it’s painful, since we manage the mail servers for them. It’s a never-ending battle to get the mail servers off of someone’s blacklist. To be fair to the people blacklisting us, sometimes my customers put things in their mail blasts that look like spam.
If free.fr is blacklisting you or rejecting your mails, there may be a config problem with your mail server or the content of the mails could be mistaken for spam.
I volunteer Dimme to help you fix it, just tell him you need someone for a FI assignment! 
Of course DKIM (a system which proves an email came from the owner of the sending domain) is free; you just need to pay someone £xxx/day to set it up on the server 
But that won’t solve it. EuroGA uses a 3rd party SMTP server for sending emails – because sending emails directly from our server makes it a lot more likely for them to be blacklisted. The server we use is a company which would normally make an effort to stay off blacklists.
Re free.fr etc – see further back the thread. Translating the email to French solved the problem completely Now, it would be a poor use of the donated funds to implement that for forum notifications
Blacklisting is another issue. Not a lot one can do if somebody joins the forum and then reports euroga.org as a spammer when they get the confirmation email. Had that just the other day. This is why if I see any bouncebacks I tend to remove that profile. Obviously I have no way to notify him. Sometimes it happens with a real contributor in which case I post it in the thread.
The forum server can be configured to use any SMTP AUTH server for email sending. If someone here knows of a free one which does DKIM and can do up to say 10k mails per month, and has staff dealing with blacklists, let me know. There aren’t many… or any, probably.
