If you have repositories other than ActiveState's included, there's a bug which makes installing via a command line such as

   C:\>ppm install Whatever-Package
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not do what you want. Installing via the GUI works OK in this respect.

The old interactive command-line interface isn't available in ppm4. However, you can issue individual sub-commands via a DOS prompt; see

  C:\> ppm help
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for what's available. For example, adding repositories can be done through

  C:\> ppm rep add alias_name http://wherever.org/ppms/
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as well as through the menu Edit -> Preferences -> Repositories of the GUI.