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A .tar.gz file is a compressed archive similar to zip Zip and RAR files. To extract .tar.gz files on Windows use 7-zip (freeware) or Winzip (commercial). After 7-Zip installed, try to open your .tar.gz file. 7-Zip will start up and decompress the archive. And if it still doesn’t extract, do it manually via the context menu: right-click on the archive and choose one of the “Extract” options.
Mac OS and Linux OS operating systems can handle .tar.gz file by default. In OS X Just double-click the archive and it will extract to a folder of the same name.
Using any FTP software upload all files.
Using With any FTP software upload all files and folders from the '../extension_name/code/extensions/' directory to 'extensions' directory in your AbanteCart website root folder.
After upload go to Admin
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→ Extensions → All Extensions section
Find your extension and click install button.
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Configure Installed Extension. You need to set the settings and enable extension. Extension An extension might have required or optional extensions in the package or separate.