The documentation portal is undergoing maintenance. During this period, you can't create any new user credentials. If you do, you'll need to recreate the user credential after the maintenance period ends.
Informatica MDM Hub uses an administration source system for manual trust overrides and data edits from the Data Manager or Merge Manager tools, which are described in the
Multidomain MDM Data Steward Guide
.
This administration source system can contribute data to any trust-enabled column. The administration source system is named Admin by default, but you can optionally change its name.