Help with Sony Xperia Compact photo uploads

[popeyewhite]

As in the title. Whenever I upload files to my pc from my Sony Xperia phone and view the jpegs in Microsoft Office they appear full size but sideways. When I rotate them to the correct way up the jpegs shrink to some kind of vertical letterbox. It does this with every jpeg uploaded from the phone and it's maddening.

Anyone any ideas?

Holiday photo uploaded from normal camera:

Photo uploaded from phone:

You can see the jpeg above is half the size of the top photo taken with a camera. Why is this?