Cause
There are 2 possible reasons for this error message:
1. Your tenant is used for the development of customer-specific solutions
(One-Off Add-On).
Your user is assigned to a PDI solution and therefore you
can only create fields in the Cloud Applications Studio. You can only create
extension fields using the key user tools if you are not a PDI developer. Once
any user opens the PDI Studio the respective user is assigned to the PDI
solution.
2. Your tenant is a partner development tenant.
Since this system is a
partner development system the field extensibility is only possible in the Cloud
Applications Studio not in the key user UI (User Interface).
If the cause of the error is reason 1 you can solve this issue as
follows:
In order to use the standard field extensibility functionality you need to
create a key user which is not assigned to the PDI solution or change the access
rights of an existing Business User.
Please note that this user needs to be assigned to the Application and
User Management work center and the Flexibility Change Log view in
order to be able to use the field adaptation.
This user should not be assigned to Partner Development (ID:
PDI_PARTNER_DEVELOPMENT) and Development (ID:MAI_DEVELOPMENT).