What am I doing wrong?

I upload a photo, and in the gallery view, it's rotated 90 degrees to the left. I click on it and it's in the correct orientation. When I copy the link for the correct orientation, and post to a forum, it shows up 90 degrees to the left for others, but I see it in the forum correctly.

 

Any idea?

 

P.S. My apologies if this has already been addressed.

I've had this a couple of times - for me, it seems to be connected to the particular software I used for the final adjustment and save. If you re-open the image in different software, rotate it left then right until it is correctly oriented and re-save it before uploading it, this may work. YMMV.