Error: "The status of this change number does not allow you to set it to active."

You try to activate a change number in ECTR:

It fails with this error:

E02514 = Der Status dieser Änderungsnummer erlaubt Ihnen nicht diese aktiv zu setzen.
E02514 = The status of this change number does not allow you to set it to active.
E02514 = 此更改號碼的狀態不允許您將其設為啟用中。
E02514 = 不允许将此更改编号的状态设置为活动。

Cause    

There exists a frontend configuration to define which status is allowed for the change number to set it active.

Solution

Change this file: \customize\config\default.txt

# Only change masters in a certain status are allowed to be set to active. This
# will be checked on startup as well.
 
plm.ecm.status.active = 01; 02; 20