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2. Upload Registration Key to the Host where SubGit is installed.

Upload the key you have received to the server where your repository is located. You may upload the file, or copy and paste key file contents to the file on the server side.

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Note the use of the sudo command above. Superuser privileges are needed to store key securely. On Windows OS you may need to ensure that register     command register command is run on behalf of the Administrator user.