ThreatSwitch sends transactional emails to users for a variety of purposes including password resets and regular notification emails. Particularly for customers without single-sign on enabled, it is critical that emails and their content arrive to user inboxes in a timely matter with their contents intact.
Emails not arriving at all
If users are not receiving emails from ThreatSwitch, the most likely explanation is an IT security setting preventing emails from coming through. In these cases, it is important to reach out to your security team to whitelist all emails from app-mail.threatswitch.com.
Emails arriving with adjusted links - "Password Reset Loop"
For users stuck in a "loop" resetting their password, this often indicates that an email security policy may be dynamically adjusting and protecting inbound URLs. In these cases, please see this article.