I now experimented with windows registry, but I deleted a "Create new folder..." from the context menu. Now, I have a little problem; in which registry hive is this point stored? I want to restore "Create new folder..."
The question is mostly not for developer. Nevertheless the part of registry which are responsible to create a folder you will find here:
HKEY_CLASSES_ROOT\Folder\ShellNew
It is of course not the only part which you could delete/rename to make the corresponding item in the context menu disappear. I general HKEY_CLASSES_ROOT part is the place which mostly responsible for the problem which you try to solve. It you want to examine your problem more exactly the Process Monitor could be helpful for you. You should have a little experience in setting of filters to reduce the output which you need to analyse.