How can the issue of "sendmail_from" not being set in php.ini be resolved in PHP?

The issue of "sendmail_from" not being set in php.ini can be resolved by setting the "sendmail_from" directive in the php.ini file to a valid email address. This directive specifies the email address to be used as the sender for mail sent from PHP scripts. By setting this directive, you ensure that emails sent from your PHP scripts have a valid sender address.

// Set the sendmail_from directive in php.ini
ini_set("sendmail_from", "your_email@example.com");