Issue Regarding Yahoo and Microsoft Mail Delivery
Last week we noticed that mailgun has lot of mail bounces from outlook mail address, because the mail delivery IP had been blocked. Usually mailgun fixes these issues automatically, but the issue was not solved after several days, so we asked them to change the IP. They refuced to do it because our bounce rate was high. This was a given as mailgun was mainly used to confirm valid mail address.
To fix it one option is to deliver mail by ourself, but since our server is IPv6 only, this won't work.
Second option is get our bounced rate back down by adding a notice in the registration page and making the backend validation more tougher. Which we took this option and while some users used a tempary email address(which is okay) some users were still adding non-existing email address.
To combact it, now we will send confirmation email by checking out the email address manually. This will take upto 24 hours. Also the upload page has been enabled to all users, so they can upload images without registering.
The issue is fixed now but to get the bounce rate down, we will keep verifying accounts manually. -2019/02/01
We will add a update when this issue is fixed.