Word and PPT docs showing text as "garbled symbols" in Confluence 6.6 (on CentOS 7.x)

[OneTech IT]

We are running Confluence 6.6.0 on CentOS 7.x (server core version).

Our users are noticing that when they upload Word 2013/2016 format .docx or .pptx files and then try to view them in browser, they show as garbled symbols and not text.  This is leading me to believe that my core OS doesn't contain the necessary fonts in order to properly render these document via HTML. 

The documents are using standard Office 2013/2016 suite fonts (i.e. Calibri, etc.)  

Is there a way for me to know if my core OS even has the correct fonts installed in order to properly render these documents in a browser?   If I download the document locally, I can open it and it reads just fine, so this definitely seems to be incompatible font related.

[Lei Wang]

Hello,

Please try the following command in CentOS7 to verify the installed Fonts such as Calibri.

[root@atlassian ~]$ fc-list | grep "Calibri"