As an admin, you can choose to disable replies to announcements for all courses in an account.
To manage comments, you can set the default value but allow instructors and sub-account admins to enable comments as necessary, or you can set and lock the setting for all courses and sub-accounts. The checkbox settings at the account level are passed to the sub-account and course levels as default values.
Note: Courses created before the option is applied will retain their settings until it is changed at the course level. Courses created after the option is applied will inherit the account level setting, which will persist until it is changed at the course level.
In Global Navigation, click the Admin link , then click the name of the account .
Disable Comments on Announcements
In the Account Settings tab, locate the announcements options.
To set a default for the entire account so that comments are automatically disabled for announcement comments in each course, click the Disable comments on announcements checkbox . This option applies immediately to new courses. When enabled, all announcements show as closed for comments, but instructors can open individual announcements as necessary. Instructors can open Course Settings and remove the option completely for all new announcements.
If you want to lock the default setting for sub-accounts and courses, click the Lock this setting for sub-accounts and courses checkbox . This option does not allow instructors to open any individual announcements or remove the limitation in Course Settings.