Hi,
not sure about the variation CK Reddy described, I have never got that working (maybe he can explain a little bit more detailed), but what always worked for me is that the HU is automatically created in the inbound delivery in EWM already. This way the HU information is already there when you start the WT creation.
Requirements: you have a packaging specification (you wrote you got that). In that one on the packaging level the flag "HU creation" must be set.
Then you need to check the determination procedure for this packaging specification. This determination procedure must be assigned to the document type of your inbound delivery (what would be INB / PDI in the standard settings).
Brgds
Juergen
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