Performing Automatic Customizing
On AS ABAP, you have to perform automatic customizing to be able to use the Business Process Engine.
Perform the following steps in your AS ABAP system:
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1. Log on as user with SAP_ALL rights (you cannot use DDIC or SAP*).
2. Call transaction SWF_XI_CUSTOMIZING to perform basic customizing. This transaction sets all required technical settings.
The screen Automatic Workflow Customizing appears.
3. Make sure that the Maintain Runtime Environment node has a green check (not a red cross).
If there is a red cross, do the following:
a. Select the Maintain Runtime Environment node.
b. Choose Perform Automatic Workflow Customizing.
The system now performs the automatic customizing including all sub nodes.
4. Choose Maintain Definition Environment → Maintain Prefix Numbers.
5. Choose Execute.
The Prefix Numbers for Workflow and Organizational Management screen appears.
6. Choose Display <-> Change to activate the edit mode.
7. In the Available Prefix Numbers for Workflow and Organizational Management box, choose Create.
8. In the dialog box, enter a Prefix number equal to or higher than 900 and choose Save.

You need to enter a transport request according to your Transport Management System (TMS) and choose Save again.