Safe Documents is a feature for Microsoft 365 Apps for enterprise that uses the Microsoft Defender Advanced Threat Protection cloud to scan documents and files opened in Protected View. For an additional layer of protection, users can't leave Protected View until results of the scan have been determined.
Here are the expected results from Safe Documents verification:
File is currently being scanned by MDATP – This is shown while Safe Documents scans the file against MDATP. Maximum file upload size is 60 Mbs.
Error in file verification – This error is shown if there are issues verifying the file, such as timeout and network connectivity issues. Users can still turn on editing, but caution is advised.
File found to be safe – This is shown if the scan does not detect any threats, so users can turn on editing and leave Protected View.
File found to be malicious – This is shown if the scan determines the file to be malicious. Users won't be able to leave Protected View.
If the admin has chosen to override the setting in the Admin Portal, users can bypass this warning and turn on editing.