Email problem

HI. I read some topics about email problems, but there is not enough information to solve my problem (maybe my knowledge in this area is very low). I contacted my hosting provider thinking that problem is on their side, but they said that it is not. When a new user is registered, he/she has to receive a confirmation email depending on options I set on the back end, and when a user lost the password or username, he/she could receive the email about renewing the password or username but it never happened with my users whose email accounts on google or yahoo . I didn't notice that this email function doesn't work properly because I used only one outside email account which is the only one which works with the site. After that, I created some testing accounts to experiment with emails and realized that @yahoo.com, @google.com, @mail.ru and some more accounts don't work at all for receiving emails from my site. The only email address that works is @ukr.net (which was not the account when I register website on the hosting). I try to register users from the back end and from the front end with the same result. Could you please explain or provide all possible steps how to fix this problem. I am not a pro in this area, so simple words and terms would be appreciated. Thanks.

gsabrd wrote: Could you please explain or provide all possible steps how to fix this problem. I am not a pro in this area, so simple words and terms would be appreciated. Thanks.

Well first you need to provide version numbers of your Joomla/CB install and also email settings you have configured (SMTP, PHP Mail, ?) on your Joomla global parameters area.

Then you need to verify the issue using test email addresses you control.

Try and send a Joomla Mass mail and verify that it works.
Then try to send a CB Mass mail (from CB User Management) and see if that works.

If it does then there should be no issue in other CB areas.