No imported client export found

What causes this issue?

The import post-processing can find no control information.
Import post-processing requires certain control information, some of
which is cross-client, and is transported with the client transport.
There are three possible reasons why this information is missing:
The transport request was imported into several clients, and
post-processing has been performed in another client between the import
into this client and its post-processing.
The transport request has already been imported into this system, and
was imported this time without the unconditional mode (tp-UMODE) 1
(e.g.because you wanted to restart a cancelled import).
The client transport source client has been changed between the creation
of the transport request and the data export. This happens when another
action is performed with the client copy tools. Check the transport
request export log after a client export. You can only open the client
for other actions when the export has finished.

System Response

You cannot perform import post-processing or use the client.

How to fix this error?

Always perform the post-processing before you use the transport request
in the same system again.
Import the transport request again with unconditional mode (tp-UMODE) 1.
Repeat the client transport. Exporting the previous transport request
again is not sufficient.

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