This will sound really lame, so if you've already tried it, sorry.
I'm a Photoshop user since the beginning of time and I'm really sorry about their support.
But, I don't know other software programs, but I DO know the quirkiness of computers..... I went on to Photoshop.com and tried to edit a photo and had no problem, so I thought I'd have you try this....
Some people have their computers on all the time, so just in case you haven't tried this,
Shut your computer OFF. Let it rest a few minutes. Then restart it. Just open the online software to get to Photoshop.com and try again.
If you've already tried this, sorry to have wasted your time....GOOD LUCK!!