Why does the blue 'Filed in FYI" icon not show up in Outlook even though the email has been filed in FYI?

Issue

I have saved an email in Outlook to FYI but the blue Filed in FYI icon is not displaying in Outlook. When I clicked reply (to an external email address) it has not added the reply to the email thread.

Cause

Occasionally there can be delays with the updating of the Filed in FYI status of an email in Outlook.

Or, this may be because the email is not in the Inbox or Sent Items folder in Outlook. FYI monitors the Inbox and Sent Items folders in Outlook. If the email is located in a different folder to these, FYI will not be able to set the 'Filed In FYI' category.