Windows doesn’t allow user to install third party themes, but however Windows Themes Installer free portable application allows users to install a theme, remove a theme and restore defaults easily in Windows 7 and Vista.
To install third party themes user need to patch some system files with Universal Theme Patcher or UxStyle Core.After patching system files by using any one of the applications mentioned above you can easily install third party themes in Win 7 and Vista.
Using Windows Theme Installer
1..Run the tool as administrator.
2. Select the Options which you want to install from
3.After selecting the option, click on Browse and browse for file of your desired option.
4.Clicking Install Theme will install theme and replaces system files.
User can able to Restore Default System files and Remove Theme and Apply Theme shown user interface of Windows Themes Installer.
It is always recommended to create a System Restore point before making any changes.