Quoted from 'Anonymous' below (this works for me):
If your Windows Explorer view settings have the Preview Pane turned on, you will not be able to save over any existing PDF file you open since the preview will be loaded by Windows which locks the file as read only. Turn off the preview pane and you should be able to resume normal save behavior.
This also makes me wonder, when Windows gives that stupid error message that you can't move or delete this file because it's already open (and you're shouting at the computer IT'S NOT OPEN), maybe this is why. I'll see how it behaves over the next few days.
TOTALLY WORKED FOR ME :'D
Quoted from 'Anonymous' below (this works for me):
If your Windows Explorer view settings have the Preview Pane turned on, you will not be able to save over any existing PDF file you open since the preview will be loaded by Windows which locks the file as read only. Turn off the preview pane and you should be able to resume normal save behavior.
This also makes me wonder, when Windows gives that stupid error message that you can't move or delete this file because it's already open (and you're shouting at the computer IT'S NOT OPEN), maybe this is why. I'll see how it behaves over the next few days.