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doc/email-configuration.markdown

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+Email configuration
+===================
+
+User settings
+-------------
+
+To receive email notifications, users of Kanboard must have:
+
+- Activated notifications in their profile
+- Have a valid email address in their profile
+- Be member of the project that will trigger notifications
+
+Note: The logged user who performs the action doesn't receive any notifications, only other project members.
+
+Email transports
+----------------
+
+There are several email transports available:
+
+- SMTP
+- Sendmail
+- PHP native mail function
+- Mailgun
+- Postmark
+- Sendgrid
+
+Server settings
+---------------
+
+By default, Kanboard will use the bundled PHP mail function to send emails.
+Usually that require no configuration if your server can already send emails.
+
+However, it's possible to use other methods, the SMTP protocol and Sendmail.
+
+### SMTP configuration
+
+Rename the file `config.default.php` to `config.php` and change these values:
+
+```php
+// We choose "smtp" as mail transport
+define('MAIL_TRANSPORT', 'smtp');
+
+// We define our server settings
+define('MAIL_SMTP_HOSTNAME', 'mail.example.com');
+define('MAIL_SMTP_PORT', 25);
+
+// Credentials for authentication on the SMTP server (not mandatory)
+define('MAIL_SMTP_USERNAME', 'username');
+define('MAIL_SMTP_PASSWORD', 'super password');
+```
+
+It's also possible to use a secure connection, TLS or SSL:
+
+```php
+define('MAIL_SMTP_ENCRYPTION', 'ssl'); // Valid values are "null", "ssl" or "tls"
+```
+
+### Sendmail configuration
+
+By default the sendmail command will be `/usr/sbin/sendmail -bs` but you can customize that in your config file.
+
+Example:
+
+```php
+// We choose "sendmail" as mail transport
+define('MAIL_TRANSPORT', 'sendmail');
+
+// If you need to change the sendmail command, replace the value
+define('MAIL_SENDMAIL_COMMAND', '/usr/sbin/sendmail -bs');
+```
+
+### PHP native mail function
+
+This is the default configuration:
+
+```php
+define('MAIL_TRANSPORT', 'mail');
+```
+
+### Mailgun HTTP API
+
+You can use the HTTP API of Mailgun to send emails.
+
+Configuration:
+
+```php
+// We choose "mailgun" as mail transport
+define('MAIL_TRANSPORT', 'mailgun');
+
+// Mailgun API key
+define('MAILGUN_API_TOKEN', 'YOUR_API_KEY');
+
+// Mailgun domain name
+define('MAILGUN_DOMAIN', 'YOUR_DOMAIN_CONFIGURED_IN_MAILGUN');
+
+// Be sure to use the sender email address configured in Mailgun
+define('MAIL_FROM', 'sender-address-configured-in-mailgun@example.org');
+```
+
+### Postmark HTTP API
+
+Postmark is a third-party email service.
+If you already use the Postmark integration to receive emails in Kanboard you can use the same provider to send email too.
+
+This system use their HTTP API instead of the SMTP protocol.
+
+Here are the required settings for this configuration:
+
+```php
+// We choose "postmark" as mail transport
+define('MAIL_TRANSPORT', 'postmark');
+
+// Copy and paste your Postmark API token
+define('POSTMARK_API_TOKEN', 'COPY HERE YOUR POSTMARK API TOKEN');
+
+// Be sure to use the Postmark configured sender email address
+define('MAIL_FROM', 'sender-address-configured-in-postmark@example.org');
+```
+
+### Sendgrid HTTP API
+
+You can use the HTTP API of Sendgrid to send emails.
+
+Configuration:
+
+```php
+// We choose "sendgrid" as mail transport
+define('MAIL_TRANSPORT', 'sendgrid');
+
+// Sendgrid username
+define('SENDGRID_API_USER', 'YOUR_SENDGRID_USERNAME');
+
+// Sendgrid password
+define('SENDGRID_API_KEY', 'YOUR_SENDGRID_PASSWORD');
+```
+
+### The sender email address
+
+By default, emails will use the sender address `notifications@kanboard.local`.
+It's not possible to reply to this address.
+
+You can customize this address by changing the value of the constant `MAIL_FROM` in your config file.
+
+```php
+define('MAIL_FROM', 'kanboard@mydomain.tld');
+```
+
+That can be useful if your SMTP server configuration doesn't accept the default address.
+
+### How to display a link to the task in notifications?
+
+To do that, you have to specify the URL of your Kanboard installation in your [Application Settings](http://kanboard.net/documentation/application-configuration).
+By default, nothing is defined, so no links will be displayed.
+
+Examples:
+
+- http://demo.kanboard.net/
+- http://myserver/kanboard/
+- http://kanboard.mydomain.com/
+
+Don't forget the ending slash `/`.
+
+You need to define that manually because Kanboard cannot guess the URL from a command line script and some people have very specific configuration.
+
+Troubleshooting
+---------------
+
+If no emails are send and you are sure that everything is configured correctly:
+
+- Check your spam folder
+- Enable the debug mode and check the debug file `data/debug.log`, you should see the exact error
+- Be sure that your server or your hosting provider allow you to send emails
+- If you use SeLinux, allow PHP to send emails