Most of Windows 7 visual styles come with a custom start orb, new welcome center, stylish task pane and more. When you want to completely install a visual style to get all these items you will have to replace a few system files.
One need to replace Shell32.dll, Explorer.exe, OobeFldr.dll and ExplorerFrame.dll file to change task pane, start orb, welcome center and back/forward buttons, respectively. As you may know, Windows doesn’t allow you replace system files easily. You need to take ownership of a system file before trying to replace it with custom one.
In the past, we covered how to replace Windows 7 system files with the help of Seven File Replacer tool. You can also refer how to install third-party themes in Windows 7 guide to know more about installing new themes in Windows 7.
Windows Themes Installer is a portable tool for Windows 7 and Vista to apply new visual styles in a jiffy. The tool helps you replace Explorer.exe, OobeFldr.dll, ExplorerFrame.dll and Shell32.dll file quickly.
The best thing about this tool is that it also allows you revert to the default Windows 7 visual style with a click.