Methods and systems for using a flexible serialization technique to determine whether certain protected content items (e.g., software) are eligible to be installed on a target computer system during an installation procedure are described. Consistent with some embodiments of the invention, a serial number entered by an end-user is decoded to identify a product identifier that corresponds with a select folder in a folder hierarchy on a storage medium that contains various payloads for installing digital content items on a target computer system. The folder that corresponds with the product identifier includes license configuration information that specifies a set of digital content items eligible for installation, based on the serial number entered by the end-user.