The test plan must be in a transportable package.
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Start the Test Plan Management.
Choose the test plan to be transported.
Choose Test Plan → Transport.
You get a list of the objects in the test catalog in the chosen test cases.
Select objects.
Choose Transport.
The transport requests assigned to you are listed.
Choose the request in which the selected objects are to be put, and Continue.
All objects are put in the specified transport request.
Objects in not-transportable packages can be put in transportable packages. These objects can then also be transported.