■ Do you like zipfolders? Now you can have 7z-folders, RAR-folders and ISO-folders!

Windows shell is a wonderful extensible system. Using namespace extensions (NSE) you can turn anything into a folder, e.g. there are system components that browse into compressed ZIP files and remote FTP servers, presenting them like normal folders to windows explorer and compatible file managers like xplorer². There are other popular compressed archives like 7Z and RAR that could be browsed like ZIP archives, but where's the NSE plugin for this task? A few years ago I spotted a half baked project at codeplex called 7zip shell and I was hoping that it would be finished one day, preferably by someone else's labours <g> — but to no avail.

As we say in Greece, "there's no substitute for one's own nails in case of an itch", so I took the plunge and finished it myself. This 7zipshell was a good base, which I optimized and completed using some ideas from TAR Folder shell extension. The backbone that reads into and extracts files from archives is 7zip, which includes a DLL component that does all the work. The resulting Browsable Compressed Archives NSE allows you to browse into most of the archive types supported by the open source 7-zip program, e.g:

Archives: 7Z, RAR, ARJ, GZ, GZIP, LZH, LHA, LZMA, TAR, ZIPX, JAR
Images: ISO, IMG, WIM, DMG

What's the point of browsing into archives you may ask? Why not just use a specialized program like 7-zip or winrar? The answer is that windows explorer and especially xplorer² can do many things that 7-zip cannot:

Richer browsing experience (thumbnails, quick previews)
Compare archive contents with regular folders
Search for files in archives (for xplorer² and deskrule make sure you tick the "Achived content" box in search options)

All the necessary components are bundled in an installer, for everyone's convenience. After installation you can choose which archive types you want to turn into browsable folders. You can run the NSE configuration tool after installation to add/remove types.

Click to download 7z NSE (1.5MB, build 1.403)

Minimum requirements: windows Vista or later (32 or 64 bit)
It will also work for windows XP if you have windows search 4 installed

At present the plugin can extract but not compress files into archives. A few other limitations (no multi-part archives) should be addressed in future versions. You can extract individual files using drag-drop or copy paste like in any folder. To access the native tool (e.g. 7zip), right click on the root archive "folder" and use the context menu. If you want to extract all the files from an archive instead of a few only, it is best to open it with its own program.

Windows 10 made it tougher for programs to set their own associations (thanks microsoft!). Anyway after installing this NSE, you must use your control panel (Settings > System > Default apps), then select Set defaults by app, find the entry for SevenZipFolder in the list and click it; finally select Choose defaults for this program and set your desired archive types e.g. 7Z or RAR.