Email hosting said, that namecheap don't use that option.
But i have found the problem.
In joomla Global settings. When i leave the textbox empty then it works (ask a questions about...)
But the contact, registration etc... are not working.
I getting this error in my mail hosting:
Could not deliver message to the following recipient(s):
Failed Recipient: info@....
Reason: Remote host said: 553 5.7.1 <info@.....>: Sender address rejected: not logged in
And if i fill the SMTP username and password then the registration, contact form... works
So, without SMTP username, the ask a question... works
But the user registration, contact.. are not working
