The Entry Key is a unique identifier. The ID is used to identify the license. Normally the unique ID is the license file ID or the Serial Number. If you do not have a serialised license file, then the unique ID could be the order number or the installation code (e.g. use GetInstcode and combine all installation codes to 1 string).
The Entry Key for a Serial Number / ID can be defined by the application. The Entry Key for an Activation Key is the Activation Key itself.
EasyGo or Multimedia Protector use the Serial Number as Entry Key.
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