Question
Why most of your branded links work, while occasionally some of them end up in a 'Not Found? error?
Product
Twilio SendGrid
Answer
Twilio SendGrid will block links that are using Public Link Shorteners like Tinyurl.com, Rebrand.ly, etc. That's because those services are often used for sending URLs to phishing or scam sites, and many email providers will treat emails with those URLs as spam/risky email. This behavior impact in particular our branded links.
Another possible reason for the error is a link that includes several utm parameters, or redirections to third party websites.
Keeping the above in mind, we recommend avoiding the use of link shorteners or redirections, and instead, include links to the final URL that you'd like your customers to visit.
Additional Information
If you want to know more about Link Branding, feel free to review our documentation. To troubleshoot other errors related to branded links, please contact our Support Team.