Hold Windows Key and Press R.
Type Regedit and press enter.
In the list on the left go to;
HKEY_CURRENT_USER
>Software
>>Microsoft
>>>Windows
>>>>CurrentVersion
>>>>>Policies
Then right-click on all of the
DWORDS in "system" and "explorer"
and select
"Modify..."
Change the values to 0 and
restart your PC.
Shutdown button has returned!