Tiki, in most cases, needs to be able to send email. It is possible for Admins to configure Tiki to send email using SMTP among other options (Sendmail, File (debug), Elastic Email, Mailgun, Mandrill, Postage, Postmark, SendGrid, SparkPost). See also Transactional Email Providers

SMTP

To configure Tiki to use SMTP instead of Sendmail (which is on the server)

Some web hosts prevent sending email from the web server. Ex.: to prevent SPAM. In this case, you must indicate the "real" email address used to send email. If you are behind the firewall, you can typically just indicate the server (no login required)

1. Visit tiki-admin.php?page=general
2. Select SMTP in the mail section.
3. Enter the information about your email account

SMTP using your Google account

You can use your Google email account to send your Tiki email after some settings.
From 2020 it work using the Google App Password option.

1. Log into your Google account or create one.
2. Click on the item Security and look at the Signing in to Google panel.
3. Check that Turn on Signing in with 2-Step Verification is turned on__. If it is not turn it on and follow the onscreen instructions. (https://support.google.com/accounts/answer/185839)
4. Come back to the security screen, Signing in to Google panel and use the App password panel to create a new App Password. You will have to confirm your credentials (again). (https://support.google.com/accounts/answer/185833)
5. Generate the App password, copy and store in safe place.
6. Go to your Tiki, Control Panels, General and set Tiki to use SMTP with the following settings (use your google email as username and your App Password as password:
   
   

   Click to expand
7. Save first and then test