I assume that "don't manage" means that two fr.wp users have not received email notifications for account confirmation and not that the link in the email somehow does not work or that the link in the email works but that something on the page goes wrong.

Is any information about the mail provider available (like GMail, Yahoo, Hotmail etc)?

In T130367#2133988, @Aklapper wrote:

I assume that "don't manage" means that two fr.wp users have not received email notifications for account confirmation and not that the link in the email somehow does not work or that the link in the email works but that something on the page goes wrong.

They don't receive any email.

Is any information about the mail provider available (like GMail, Yahoo, Hotmail etc)?

Good point. I'm asking them.
Thanks!

Only one answer so far: one user has a GMail account.

Second user uses GMail too.

I've a private element to add.

We also have T134059, with a former user who lost the account password. They have indicated to have used the mail recovery feature, and checked their gmail account all mail / spam folders, without success.

My understanding so far is that this task is about sending emails to newly registered accounts, while T134059 and T134246 are about resetting passwords of existing accounts via email. But T134246 could also affect newly registered accounts - we don't know yet for sure, I'm afraid.

An hypothesis is we could have a generalized reject of some of our mails by Gmail, regardless the code triggering mail sending.

We can switch back the task back to public if needeed: I've discussed the issue with the concerned user, they agree to release publicly the fact they used gmail in the past.