Locate the collection before rebuilding it
A Mac can hold more than one Apple TV media library. If a familiar home-video collection disappears after someone opens a different library, first identify which collection is active. Reimporting everything immediately can create confusion about which library should be maintained. This is a local media-organisation question, separate from whether a subscription remains active or a store purchase belongs to the signed-in account.
Use Apple’s documented library chooser
Apple describes quitting the app and holding Option while reopening it, then choosing an existing library or creating a new one. It recommends unique, recognisable library names. Each library can have its own display and restriction settings. A different set of videos or preferences can therefore reflect a different library selection rather than a change applied to the previously used collection.
Work through an external-drive example
Suppose a family keeps archived home videos on external storage and everyday viewing in another library. Confirm that the relevant drive is available and select the recognisably named archive library. Inspect a known item before moving files or creating yet another collection. Preserve the existing library files and source videos while resolving identity; choosing a library should not be used as an excuse to delete an unfamiliar folder.
Record the library context for later support
Keep a private note of the chosen library’s name and location, especially if more than one person uses the Mac. If an item remains absent, describe which library was selected and whether its storage location is available. Do not equate a successful switch with proof that every referenced file is healthy, and do not promise that a local library choice changes another device’s cloud watch history.
Questions, answered
Can different libraries have different settings?
Apple says each created library can have its own displayed content, restrictions and library name.