Why does the conferenceserver not launch the calls when starting an ad-hoc conference?

When using the conference server on an OpenScape Business with UCsuite you need to define at least one number for the conference channels.

These can be found in expert mode - Station - application suite - conferencing. Here you can enter up to 5 numbers. The best is to enter for every channel a number. People do not need to know this number, they just need to be defined.