On-call scheduling subscription link brings up the credential pop-upIssue Why the Authentication window/popup shows up when the On-Call Schedule Subscription link is clicked. Steps to Reproduce HOP to any instance with On-Call Scheduling enabled, impersonate the System AdminNavigate to On-Call Scheduling ➔ My Group SchedulesChange the filter to All, by default it will be filtered by GroupOpen any shift and within the 'Calendar Subscription' section, complete these two fields: Coverage Interval:Get Coverage for: Save or Update the record.Click on the 'Send Subscription' UI Action button.Verify the email link by navigating to System Logs ➔ Emails. The Subscript link looks like:https://<your-instance>.service-now.com/api/now/on_call_rota/rotaUserICalendar/287ee6fea9fe198100ada7950d0b1b73/c8fdd9f7db567f0078b2e64305961991/5137153cc611227c000bbd1bd8cd2005Clicking on the Subscription link, the authentication popup and displayed.ResolutionThis is a normal occurrence, as the product's documentation explicitly states that only basic authentication is compatible with calendar subscriptions. A section of the documentation addressing this is provided in On-Call Scheduling Note: To access their on-call events, users are required to provide their instance credentials to authenticate themselves when using the subscription URL, which only supports basic authentication.Basic authentication is only supported by the Calendar application on Mac OS X 8.0 or later and the Outlook application on Windows 2013 or later for calendar subscriptions.Even if SSO is implemented, basic authentication is still necessary for subscription with the URL.Related LinksOn-call subscription not working with AD accounts