Diagnosis
You have not made the basic settings for the setup of the ApplicationEnhancement Tool (AET) in the SAP GUI transaction AXTSYS. Especially ina landscape with multiple development systems, a prefix has to bespecified.

System Response
A warning is displayed.

Procedure
We recommend that you make the system settings before using the AET. Itis also possible to proceed; then the used prefix will be defaulted tospace.