When content is shared with external users, these users will receive an invitation email including a URL. There are situations where Filr can only be accessed using a secure connection, and then this URL should contain a HTTPS:// URL instead of HTTP:// URL.
In the Appliance Management Portal (port 9443) via "Filr Appliance Tools" > Configuration > "Outbound E-Mail", there is the option to "Force HTTPS links". This setting is available in Filr 1.1.0 and greater.
There was a bug in Filr 1.0, which was addressed in Filr 1.1.0 and later releases. Prior to the fix in Filr 1.1.0, these steps were required:
Copy the "parameter:ssf.secure.links.in.email=false" line from the ssf.properties file (located in /opt/novel/filr/apache-tomcat/webapps/ssf/WEB-INF/classes/config) into the ssf-ext.properties file. After this, change that setting from false to true and restart the server.