Classic Shell

Classic Shell is computer software for Microsoft Windows that provides user interface elements intended to restore familiar features from past versions of Windows. It focuses on the Start menu, File Explorer and Internet Explorer — three major components of the Windows shell. In particular, it can serve as a Start menu replacement for Windows 8 and Windows 10 systems.
Developed by Ivo Beltchev, it was first released in 2009, and has been downloaded over ten and half million times since.
Development by Beltchev has ceased, and the project's source code has been released. Development has been picked up by volunteers on GitHub under the name Open Shell.
Features and architecture.
Classic Shell is packaged as a suite of three components, all optional and independent of each other:
Classic Shell is programmed in C++. Although it modifies Windows behaviors, it does not do so by modifying or tweaking Windows registry settings or replacing or patching system files — all modifications are done using Windows APIs. It is localized into more than 30 languages, including right-to-left support for Arabic and Hebrew.
Classic Start Menu.
Classic Start Menu is a replacement for the Windows Start Menu. Features include:
Besides restoring past behavior, there are several new features. These include showing the menu next to the taskbar when it is vertical, multi-monitor support, launching multiple programs at once, custom shutdown-related actions, Universal app launching, expanding any file folder as cascading menus, and additional keyboard shortcuts. The search box can search the system path, can show partial matches, and can show all results inside the menu.
Classic Start Menu can also modify Windows 8's new UI features, such as hot corners only on the desktop without disabling them inside Universal apps.
Classic Explorer.
Classic Explorer is an add-on to Windows File Explorer, implemented as various shell extensions. It does not replace . Features include:
History.
Classic Shell began as a tool for personal use, and saw its first public release in 2009. Over time, the Start Menu component evolved to be a customizable launcher that also integrated a search box and other features of the Windows 7 Start Menu. The Explorer and IE components appeared later.
While earlier versions were compatible with Windows Vista and later, versions since 3.9.0 no longer support Windows Vista/Server 2008. Classic Shell was never popular or necessary on Vista in the first place because Vista, like XP, came with the ability to revert to a classic start menu.
Classic Shell is released as free and open-source under the MIT license.
Founder Ivo Beltchev announced the end of development in December 2017.
Classic Shell has picked up development once again under the name Open Shell and has been actively maintained and developed since 2018. Open-Shell has not been given any new features, but has fixed many bugs and issues, most caused by new feature releases of Windows 10.
Reception.
Classic Shell was a fairly popular interface enhancement in the Windows 7 life cycle but became much more widely used after the release and negative reception of Windows 8 (with its lack of a Start menu).
It has seen coverage in such publications as "Forbes", Lifehacker, Neowin, Ghacks, ZDNet, "PC World", TechRepublic, MakeUseOf, and Betanews.