No we can’t do it. Sorry but I am not getting involved in messing with anybody’s server. This is your website and therefore your responsibility.
Anyway – the problem is that instead of naming the image file userdefault.png you named it:
userdefault.png (registered users).png
I really would recommend you get some sort of developer in to clean things up. I was able to find what you had called it simply by listing the folder contents in the browser which is insecure and asking for trouble.
