mogaka wrote:

Hello;
Users with a yahoo email address do not get their activation links/emails after registration. Is this a known issue and is there a fix?

my site is www.portal.tipsonline.biz.

Thanks.

Does mass email reach these yahoo accounts?

mogaka wrote:

Yes mass email reaches the yahoo accounts. Does that eliminate joomla?

Good sign.
Now you should experiment with the following parameters:

CB -> configuration -> registration tab:
Registration email address:
Registration Reply To Email Address:

make sure both contain valid email addresses.

A few questions to try to corner the problem on why the emails get refused by yahoo:

Did you check the yahoo spambox ?

Are those from and reply-to CB email addresses identical to the joomla ones ?

Do they match your domain-name ?

Is there a SPF record for those addresses, and is the IP address of your server authorized ?

For other (fine working ?) addresses, is that From address matching the one you have set (mail server can change it sometimes) ?

What is your joomla version ?

What is your joomla email method setting ?

Did you try other method settings (Just in case to make sure) ?