The easiest solution would be to take Ownership of the files\folders in question and add yourself as a USER with Full Permissions..
Change Ownership and add Name as a USER
Select Security Tab and then ADVANCED at the bottom.
Here you can edit the permissions for existing users and\or add another..
Click "CHANGE" next to Owner at the top of the window...
Select...
1) Advanced
2) Find Now
3) Select User from list...Your user name, or any you want to add.
4) check the box "Replace Owner On Subcontainers and Objects"
5) Hit "Apply"
Close out of all of the open windows and start over with the Advanced button...
1) select "ADD" near the bottom
2) select "Select A Principal" at the top...
3) Advanced
4) Find Now
5) Select User from list...Your user name, or any you want to add.
6) Give the new user\owner full permissions...
7) Do Not check the box "Include Inheritable Permissions From This Object's Parent""
8) Select "Apply"...
Next, try deleting the folder again
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hth
Marcin