qBittorrent official forums

It seems that registering with a hotmail email address is a 50-50%.
It either works, or the registration mail gets lost all the time.

- Our site is set up correctly, it puts the new mails into the queue properly.
- Server is set up fine, checked it with multiple MX checkers. All 100% green.
- Server sends out mails, checked logs. Mail is handed over to Hotmail, which throws them into the trash.

Now for the fun part:
This is a known issue at Hotmail/Outlook and there is NO proper fix for it. Just Google "Queued mail for delivery" and "hotmail".

For now, I contacted the Hotmail/Outlook team (via some form) to get our IP whitelisted.
Hope they will address the problem fast. Meanwhile, contact me if you cannot register and I will approve your account.

And Hotmail/Outlook replied. Nothing wrong with our address.
Anyway, I will join the JMRP and SNDS services, to get more information/help for our problem.

I always monitor the logs of our server and it seems Yahoo have rejected us as well.
Have already contacted them, issue will be fixed within 72 hours.

Hotmail/Outlook should be fine on the other hand.
In the logs our server reports that we delivered the messages perfectly fine.

... status=sent ... Queued mail for delivery

Yahoo contacted me that the issue is resolved, we are green.
So every user should receive our registration letter and the subscription letters we send out. (If you subscribe to a topic or receive a message or something.)