Issue

For some files, file previews do not function properly and may show an error screen as shown below.

Resolution

Please check the following two points:

• Ensure the file does not fall under any Box Preview limitations.
  https://support.box.com/hc/en-us/articles/360044195013-Introducing-Box-Preview

• Confirm that communication with the domains and hosts required for Box services is allowed.
  https://support.box.com/hc/en-us/articles/360043696434-Configuring-A-Firewall-For-Box-Applications-and-Services

If the issue persists after checking the above points, please contact Box Support for further assistance.