About Checkout
You must check out an object before you modify the object. The process of checking out communicates your intention to modify a design to the Windchill PDM server. The PDM server implicitly locks the object, thus preventing modification by another user. The checkout process enables you to determine the configuration of the objects as well as the workspace in which to modify the objects.
During checkout, the data that defines the object and its relationships are copied to the local workspace. You can specify whether to copy the files from the PDM server to a workspace or access the files through a link. Linked files are retrieved from the Windchill PDM server only when requested by the Creo application. You can use the linked files to maintain local copies of objects that you have retrieved in a Creo session after checkout.
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If you have multiple workspaces, a checked-out object can only be modified from the workspace where it was checked out. The object is inaccessible from any other workspace until it is checked in.