Rotated Photos

Photo Paint X6 full version, W10.

For some reason today Photos opened in PP are being rotated 90 deg when opened from photo viewer. It's never happened before and is driving me insane. Anyone know why it has suddenly started doing this and how to stop it. Most answers one the net seem to think it because the photos were taken on a phone but my weren't they were taken on my trusty camera I've been using for 7 years.