I have been struggling for this issue for months. I have a website, that the registration requires email authentication. I did a check (daily), the statistics are quite interesting. Everyday, out of 300++ users sign up, only 50 - 60 % are activated. There is one time, when my website traffic suddenly burst up, I have around 1000++ users signup per day, and it last about 1 week. However, the statistics still show that only 50 - 60% users are activated. I dont think its a coincidence, since the statistics always shows 50 - 60% users are activated. (I check my database everyday)
I guess, maybe my emails were treated as spams, and thus not able to reach the recipients. But I wonder, how many emails does FaceBook send per day? For me, I received about 20 - 30 emails from them everyday. We all know that, facebook has millions of users, I cant imagine how many emails were sent per day. Those mails are not considered spams?
Is my hosting company responsible for this? or its my script/programming problems?
Here is my server information: OS: Windows Web Server: IIS 6 Web Languages: HTML, PHP, JS + Jquery Mail Server: MailEnable Standard SQL: MySQL 5.XX
Let me know if you need more information