Windows doesn't show yes/no tab

Hi, first, i am sorry for my english, it isn't very good. second, there's a problem and i don't know what to do lets say i want to delete something and this happens: right click on a file, press delete and file is deleted. but this problem exists only with files which were in my computer, before i installed windows. can someone tell me how to enable "confirmation tab" (i don't know how to call it ) by the way on one drive appeared folder named "1a47a021c2d97d68c4f8ad", which contains several strange folders. can i delete this folder? thanx for help

Display delete confirmation dialog is checked, and my problem still exists :)

So you get no warning at all...the file just disappears? Try Brink's suggestion and post back. By the way, your English is just fine...definitely understandable.

Brink, that's not one.

As i understand this problem is related with system. i tried changing security settings, owner settings, user accounts (in computer management), nothing helped, so if someone knows more serious solution (no offense), pls help me :)

Brink,
there are no restore points, which i can use. also i don't use system restore, so it won't help.

i am losing my last hope... i know one solution but it isn't very good: as my friend said: "I smell format"

So i created a new administrator account, but it can't even go into drive D: where are my all files (access is denied), although a simple user can.