Email notifications do not support many custom URLsDescriptionEmails that include links to records such as KB articles include the instance original URL but do not call the custom URL by defaultSteps to Reproduce 1. Have an instance with many custom URLs2. Attach a KB article to a ticket3. It will generate a notification either custom or OOB4. If the notification prints previous comments, the one that contains the KB article will have the instance name hardcoded in the recipient's email client (outlook, gmail, etc).WorkaroundThis problem is currently under review. You can subscribe to this Known Error article by clicking the Subscribe button at the top right of this form to be notified when more information will become available.Related Problem: PRB1939249