Thank you for your post.
We have had some issues in the past with custom icons showing in WebDirect's Launch Center, especially when SSL was enabled. Many of this issues issues have been fixed, so you may want to verify your Server is up to date. If you could provide the following information:
What version of FileMaker Server is installed? (13v9, 14.0.4b, etc.)
Is SSL enabled and are you using a custom certificate? (or default certificate?)
Thanks for your reply.
We are using FMS 18.104.22.1683 on a Windows server (2012R2)
SSL is enabled and we are using a Comodo Elite SSL Certificate.