You can send announcements to all users in the domain. This can only be done through the Administration tab, and you must have administrative rights to send a domain announcement.
Click the Administration tab.
Click the Administration link.
Click the Announcements tab.
Click New announcement. The Post Announcement view displays.
Enter the subject for your message.
If the announcement should have a Start or End Date, click on the corresponding checkbox and select the date(s). If not, the announcement will be posted indefinitely.
If the message should be posted to all subdomains of this domain, click to place a check in the Domain-wide checkbox.
Enter the message text. You may use the Formatting toolbar to format the message.
You can also add equations or images to the announcement.
Click Post. The announcement will be visible on the specified start date or immediately if no start date was entered.