Problem with Icons

On user’s PC all the Icon are black. I’ll try it with “Add/Remove”, refreshing, restarting, changing desktop themes, checking the viruses and it doesn’t work.
Every Icon on PC is black:on toolbar,when you open the new window and want to select inside some program,…

Can anybody help me and tell me how I can get back those Default Icons?

Please, if anyone know, contact me either on this site or send me a mail.

Thanks in advance,
Zinka