About a Locked Workspace
You can lock a workspace to maintain the state in which the workspace is exported. Locking a workspace prevents unintended changes to the workspace cache and helps minimize the conflicts that may arise when the workspace is imported back.
You can also unlock a workspace after exporting it.
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You can lock or unlock only a single workspace at a time.
Locking or unlocking a workspace is possible only if you are using a Windchill 8.0 and above server.