Method 1: Steps to Unlock & Unhide Windows 7 hidden locked Themes
1. Unhide the Windows 7 System and Protected Operating System files from Windows explorer -> Organize -> Folder and Search Options -> view tab
2. Navigate to C:\Windows\Globalization\MCT.
3. Open a MCT-(AU, CA, GB, US, or ZA) folder for the regional theme that you want.
NOTE: AU, CA and ZA regions all have the same themes though.
4. Open the Theme folder in the selected region folder.
5. Select the .theme file to use it.
NOTE: Once you select a .theme file, Windows 7 will save it so that you will be able to change or select this theme again from within the normal Personalization window location.
6. Hide the Windows 7 System and Protected Operating System files.
7. Enjoy your new regional themes!!
love Method 2: Using windows 7 Search (Simplest Method)
1. Go to \Windows\winsxs Directory
2. Search for *.theme.
Unlock & Unhide Windows 7 Hidden Themes for Regional Countries
3. Double click themes with name in the format of XX to apply and save the theme.