When I create an email in FYI as "Draft in Outlook" and attach a number of files, the correct number of files shows in FYI, but in Outlook it is not showing all the files that I attached.
This is intermittent and relates to how Outlook is handling the email. It can occur if all the files have not downloaded to Outlook when you open the email.
Close the email so that Outlook can finish the attachment sync.
Wait a few minutes and then re-open the email and all attachments will display.