Can't change profile picture on Google+

"There was an upload error. Make sure that you upload a JPG, GIF or PNG file and try again."

I get this motherfucker of a message every single time I try to upload a profile picture. I've tried ALL compatible picture formats and different sizes on different browsers and repeated that on my other computer as well. Absolutely none of the perfectly square and compatible profile pictures in my gallery work. I'm fucking speechless.

It would be nice to hear if I'm not the only one with my problem.