I cant delete windows old folder win 8

You have to take ownership of the folder structure for win.old....
Once you are an owner (making sure you apply the permissions to all subfolders as well) add the everyone to have Full Control over the folder (I know some might say this is not needed, but I have run into issues when this step is skipped) once that has applied to all subfolder and files as well you shoul dbe able to delete the win.old folder.

Good luck and let us know how you get on.

the have a registry mod call take ownership it works great for locked folders and files. here is a link to it http://www.howtogeek.com/howto/windows-vista/add-take-o... it works just open it and then right click on the folder you want to remove and click take ownership then delete..