We have pages that display RSS feeds using the RSS macro in conjunction with the Page Tree plugin that can't be rendered when using Internet Explorer. It first prompts the user "Do you want to display the nonsecure items?". Then it gives the error popup "Internet Explorer cannot open the Internet Site https://someurl. Operation aborted". Then it gives the generic "The page cannot be displayed" page. This problem doesn't occur with Firefox. We are using the RSS macro as such: {rss:url=http://www.iona.com/rss/iona.xml|max=5} This one particular RSS macro works just fine however: {rss:url=http://www.oracle.com/rss/rss_ocom_pr.xml|max=5} Also, our Confluence instance is hosted via SSL (https://...) I have attached the page layout of the space in question that calls the Page Tree plugin.