The folder `http://sourceforge.net/projects/opencvlibrary/files/opencv-win/` is stale and wasn't updated since 2018. The parent folder `http://sourceforge.net/projects/opencvlibrary/files/` has fresh windows install exe files.
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-# Launch a web browser of choice and go to our [page on
- Sourceforge](http://sourceforge.net/projects/opencvlibrary/files/opencv-win/).
+ Sourceforge](http://sourceforge.net/projects/opencvlibrary/files/).
-# Choose a build you want to use and download it.
-# Make sure you have admin rights. Unpack the self-extracting archive.
-# You can check the installation at the chosen path as you can see below.