7-Zip plugins\Proxy7z

Thanks to extremely high compression rates the 7-Zip application and its 7z format have become widely popular today, and are effectively a de-facto standard today along with zip and rar formats. Many compression utilities and file managers support unpacking of 7z archives "out of the box".

Among its other features, 7-Zip supports its own plugin system. Any developer can create a plugin and tell 7-Zip to use it to open various data formats as archives, for instance, ExFat disk images or images of CD-discs. Another possible application is a plugin-codec that can be used to pack data into a standard 7z file. For instance, to apply the increasingly popular Zstandard compression method.

Unfortunately, the majority of authors of archivers and file managers provide only minimum support for the 7z format by using 7z.dll or 7zxa.dll libraries and completely ignore 7-Zip’s ability to leverage third-party plugins. In such a case, all 7z files created with some optional compression methods will be inextricable in those applications. As a solution, we offer using Proxy7z library.

Proxy7z is a library that "deceives" an application that uses 7z.dll or 7zxa.dll libraries. Proxy7z undertakes all third-party plugins functions, while the deceived program has no idea that it now can understand much more compression methods.

The general algorithm of using Proxy7z is:

  1. Rename 7z.dll or 7zxa.dll used by the program to 7z.dll.bak or 7zxa.dll.bak respectively (in case you decide to revert back).
  2. Download the archive file with the library using the link below.
  3. Extract 7z.32.dll or 7z.64.dll from the archive (depending on the whether the app is 32-bit or 64-bit) and copy it to the folder where the original 7z.dll or 7zxa.dll was.
  4. Rename the copied file to 7z.dll or 7zxa.dll (depending on which one was used by the program).
  5. In the same folder create a folder named "7zPlugins"
  6. Copy 7z.dll from the 7-Zip to the 7zPlugins folder. Remember to copy the correct 32/64 bit version! If the program uses 7z.dll originally, you can copy that file instead.
  7. Copy all plugins you need to the 7zPlugins folder.

After that, the program will work with Proxy7z just as with the original library, and Proxy7z in turn will address all queries to corresponding plugins. For the program, the entire process is completely transparent.

Current version

  • Version: 1.0
  • Distribution package size: 50 KB
  • Distribution package release date: 08 May 2020