I have set an workflow , which will take owner from other module and assign it to a new record.

However, if user has been deactivated, deluge can get user info as normal , while It will pop up error when it is assigned to the new record's field.which interrupt whole workflow run and seems it cannot be prevent as there is not any field to show the user that I get is an invalid user.

Do you have good idea to prevent an invalid user being assign to new record?