Email service providers and IT departments can implement safeguards to prevent spammers from using your email address as the “from” value in a spam email (making it look as though you sent it).  This spamming technique is called “spoofing“.

Major email providers widely implement these precautions. However, some self-hosted and corporate email systems do not.

For this reason, FollowUpThen offers various levels of sender validation to accommodate users with different email configurations and security needs.

On your general settings page, these options are listed by each email address associated with your account:

• None: We will not validate the authenticity of the “from” email address.
• Warn (default): If an email is received without validation, a warning message will trigger.
• Block: Drop any emails that do not pass sender validation check.

To pass sender validation, either SPF or DKIM must be implemented, along with a spam filter and anti-virus test that ensures the validity of the message.

If you are uncertain if your email provider supports one these methods of validation, you can set your preferences to “warn” and look for the resulting trigger. You can also contact your email provider.