My mom has an iPhone 4 (or 4S) and she has taken so many photos that there are 0 Bytes space left.
I can't install apps to delete files on the phone directly.
I can't move files via USB.
I can't delete files via USB.
Windows 7 shows the "Deleting ..." window but nothing happens (not even on a single photo).
So how can I delete all those photos (backups done) or even better the whole phone including iOS?