Troubleshooting Embedding a 3rd Party Calendar into SharePoint


This article provides a possible solution when receiving the error "Embedding content from this website isn't allow, but your admin can change this setting. They will need to add '' to the list of sites that are allowed.” while trying to embed some 3rd party calendars into SharePoint.


The admin referred to in the error message isn’t Virginia Tech’s tenant level Microsoft 365 (M365) admin. It refers to the SharePoint site admin or owner. That individual must add the domain where the calendar is hosted to the HTML Field Security setting for the SharePoint site.

  1. The owner or admin of the site must log in to the site.
  2. Click on the Gear icon at the top right-hand corner of the page.

  3. Click on Site Information

  4. Click on View all Site Settings
  5. Click on HTML Field Security under Site Collection Administration

  6. Add the domain (for example, in the Allow iFrames from this domain: text box.
  7. Click Add
  8. Click OK