Some idiots (Белый ветер цифровой) sold me device with retail mode enabled. You can’t do anything with device like this.
And I was too lazy to go to those guys and say what a bunch of motherfuckers they are.
Luckily, I was able to find a documentation on this application. Here it is, with pictures and so on.
In short, the password to disable samsung dcr retail mode is M729Q16K8546 .
Guys, I only happened to buy this camera with retail app. I can’t help you with any other device - I both don’t have them and expirience dealing with them.