Hi Sirko,
you need to configure this Setting:
"Neues Update veröffentlichen "Das Update immer in der WSUS-Konsole sichtbar machen..." oder "Immer wählen".
Than restart WPP or do click the reconnect button.
After this you should be able to delete the empty product/category.
HTH
Norbert
PS: Mentioned here https://wsuspackagepublisher.codeplex.com/discussions/471290
you need to configure this Setting:
"Neues Update veröffentlichen "Das Update immer in der WSUS-Konsole sichtbar machen..." oder "Immer wählen".
Than restart WPP or do click the reconnect button.
After this you should be able to delete the empty product/category.
HTH
Norbert
PS: Mentioned here https://wsuspackagepublisher.codeplex.com/discussions/471290