Hi Christian.  I've been testing this on a 2008r2 server, and the icons are showing for me, no matter what I change in IIS.  Have you tried clearing the cache/history in Chrome?

Yes I did clear the cache/history. I can see in the website source where the icons reside and all of them are there. I wonder if the relative path to those icons is not being resolved correctly. I did the upgrade over my existing SM 15 site, could that cause an issue?

Hi Christian.   We always advise against installing on top an existing version.  This is especially true of installing SmarterMail 16 on top of version 15, as these use two very different technologies.  

 

I would recommend opening a support ticket so that we can take a look into this.

 

 

I found the problem.  The missing icons were throwing error messages to the js development tools console.  After troubleshooting further I found that the "Content-Security-Policy" on my server didn't contain a tag for "font-src"  after setting the tag to "font-src 'self' 'unsafe-inline'"  it worked!!!!

 

Hope this helps someone in the future.

Thanks for the follow up, Christian. I'm going to mark this as "resolved" as you found the fix.