When adding an exception to the SSO list, the following message is seen:
The Subscription could not be saved.
Please correct the errors identified below and click one of the "Save" buttons.
Further down, the following error is seen:
The following users do not exist in your subscription and have been removed from the list: [email protected]
Checking the subscription user list shows that the user does exist.
This can be caused when there is an unexpected whitespace character at the beginning of the username. This can happen when the username was copied and pasted from a rich text source such as Microsoft Excel.
Retype the user's username and ensure that there are no whitespace characters in the login.