As an IT at my company we have random users who cannot use the “preview” option because it is greyed out. No this is not due to multiple things being checked. Strangely enough on the same machine I can log in as an administrator, log into the same users IFS account and the preview button is magically available in the same screen.
After searching for quite some time, I haven’t found an answer.
For context, we use Bluebeam for our PDF viewer, however I don’t believe this is the issue as the problem persists even if I use edge or Adobe.