Enabling file preview

Allows O365 users to preview PDF documents while blocking the download and saving of local copies on any device.

If a user attempts to download a PDF file they will be redirected to a preview of the file inside of the web browser. For downloads of all other files other than PDF, a user will be presented a block message.



File Preview is only available when a policy is configured for Any as the only Access Method and is currently only supported for O365.

Selecting File Preview will override the Download DLP options as this policy action will only preview files.

Use Case Example: A company that would enable File Preview is looking to prevent users from downloading (whether inadvertently or intentionally) files from the cloud application. Thus they are not concerned with users being unable to download certain files while blocking other files. A standard use case would be to create a policy to allow the download of files to managed devices while blocking all files downloads to unmanaged devices (but allowing those files to be previewed in the web browser).

To enable File Preview create or modify a policy line on your chosen app:

  1. Make sure that Access Method is set to Any.

    If you have selected other Access Methods such as ActiveSync, Basic Auth or SSO Auth, the File Preview option under the Actions dialog will not be available.



  2. Click into the Action column and select File Preview.

    Notice that the Download DLP section collapses as those Download DLP options become invalid.

Once you have saved and applied your policy, users will be unable to download files from the cloud application.

  • When they attempt to open a pdf file, a File Preview will be shown in the browser that is encrypted which will block the user's ability to save a copy or download the preview.

    The preview link in the HTML container will only be valid for 10 minutes.

  • When a user attempts to download a file that can be previewed through Forcepoint ONE SSE, the user will be redirected to a new browser tab displaying the preview of the file instead.

    If a user attempts to download a file that cannot be previewed through Forcepoint ONE SSE they will instead be redirected to a new tab showing a block message.





See Known Limitations page for more information.