The project that I'm currently working on, is large scale. I'm using email activation method for user registration system: Sending activation code via my shared hostings smtp server to users email address after successful signup.
During tests, I have noticed that, it sends emails to famous mail services like gmail, live without any problem and receiver gets message directly but when I tried to send email to well known email server (rambler.ru), the swiftmailer script (that I'm using to send emails) returned success message. BUT another side didn't received any message. That's big problem for me.
At first I thought maybe that's scripts problem. Tried phpmailer too. No success. Then tried to send from Outlook to that server for testing purposes. The user on rambler.ru received message with very big delay. I'm using shared hosting on Hostgator. There might be users that using rambler.ru server, and I dunno if that's one and only server that occurs such problem.
How to deal with that problem? I know that, I can send from live or gmail servers with "fake" from name. But another problem, is there will be probably daily limit or something like that. Any suggestions?