TL;DR: Install Package Control manually. Add the proxy settings to the configuration file as described in step 2 below.

Today I've had to install Sublime Text 3 again on a new computer. Package control didn't want to install due to my proxy settings (I was getting a 407 error code - Proxy authentification required). I managed to do it with two simple steps:

  1. Install Package Control manually. At the time of writing this post, the process is simple:

    1. Click the Preferences > Browse Packages… menu
    2. Browse up a folder and then into the Installed Packages/ folder
    3. Download Package Control.sublime-package and copy it into the Installed Packages/ directory
    4. Restart Sublime Text

  2. Set the proxy coordinates in the settings:

    1. Click the Preferences > Browse Packages… menu

    2. Enter the User directory

    3. Open Package Control.sublime-settings

    4. Add the following JSON entries to the file:

      1. http_proxy - your proxy address/port (x.x.x.x:port)
      2. proxy_username - the user name for authentication
      3. proxy_password - the password

Note: Your proxy password will be stored in plain text so you might want to set up file permissions...