[SOLVED] How to setup a 'Send e-mail' function?

Are you using any 3rd party plugins that could affect the email form? Like CB Public Mail? The error message implies the entire mailer function failed. Does it fail for every user to user email or just a specific user? Ensure the email addresses are absolutely valid.

1) Fails with every user.
2) ABSOLUTELY sure that email addresses are valid.
3) I use no additional mailing plugins for CB.
4) No matter if Latin/cyrillic characters in email topic and body.
5) No matter which category sender and receiver belong to - super users, registered users etc.

Strange, please PM backend super administrator login credentials as well as FTP login credentials so can debug further. FTP is needed for me to add debug code to the mailer and see why it errors.

Hey Kyle!

You'll be surprised but miracles happen .
After your yesterday request of admin login details, I was trying to figure out which is the best way to give you an access without any risk of data/site availability loss. Finally I decided to upload the site copy to a testing subdomain in order to make it separate form the main site. A new database with imported contents was a part of it too. After I've done this, I've double-checked if these user emails work on the subdomain - and they worked! (while on the main site they still did not). And the only difference between these 2 site copies was a database name and user.

And you know what? I've created one more clean database, imported the contents and switched the site to this new one - after that everything works fine with the emails!

So, even without knowing a reason, I've managed to solve the problem. And in fact you helped me a lot - if you wouldn't request a super admin access I wouldn't do all these moves.

So thanks very much! If you have any ideas about it - share with me please.

That's pretty strange. My guess is the database went out of sync or for some reason the "email" column ended up in _comprofiler making it seam like users had no email addresses. Anyway, glad you got it fixed!