Following that, go to the File Block Settings tab and make sure that the Open selected file types in Protected View setting is selected. If so, tick the Open checkbox of PDF Files.

Here you need to ensure that the Open selected file types in Protected View option is selected. Then, tick all the Open checkboxes of old Word versions. Let’s learn more about these steps.

Whenever you open one of these file attachments or downloads, Word opens in something called Protected View. This is, believe it or not, a feature, even if it comes across an annoyance.