Every IBM® Rational® Rhapsody® configuration
item can include references to other configuration items (CI cross‑references).
Once a configuration item is moved to another workspace, some of its
references might no longer exist in the new context. These dangling
references are called unresolved references. For example, if
you replace an existing package with a newer version and the new package
does not contain an item that shows in a certain view, references
to that item will be unresolved.
The only configuration management operation
possible on unresolved elements is Check Out (and Fetch in SCC mode).
The Synchronize operation can resolve an unresolved element.