Microsoft Outlook 365, 2016 or 2019 error message "The file is corrupt and cannot be opened" with Word or Excel Attachments

If you are getting any of the following error messages with Microsoft Outlook 365, 2016 or 2019 when trying to open Excel or Word attachments:

The file is corrupt and cannot be opened
Word experienced an error trying to open the file
Microsoft Outlook (Protected View) has stopped working

Which then could prompt you to try some suggestions:

Check the file permissions for the document or drive
Make sure there are sufficient free memory and disk space
Open the file with the Text Recovery converter

These errors message show up as Microsoft Office Trust Settings which are preventing you from opening untrusted files.

Follow these steps to resolve this issue:

1. Open Microsoft Word

2. Go to File > Options > Trust Center

3. Now click on Trust Center Settings

4. Click Protected View in the left pane

5. Click OK to save changes in Trust Center window

6. Now uncheck the box: Enable Protected View for Outlook attachments

7. Click OK in Word Options and then close word

You will need to repeat all the above steps in Microsoft Excel as well.

Now attempt to open an email with a Word document attachment.