There can be times when an organisation falls into losses to such a point that continuing operations hurts the company. At such a point, generally all the employees are laid off as there is no other option. Such news can be devastating although such actions are often anticipated in advance. One of the ways to communicate it to employees is through email.
Start off the letter with the bad news but make sure that it is delivered as mildly as possible. Let the employees know about the situation and the reasons behind the shutdown. The tone should be a low and you do not want to sound excited with your words.
In the next paragraph, let them know how they will be paid and when the whole thing comes to an end. Make sure that everything is crystal clear.
In the last paragraph, appreciate their services for the company and wish them luck for their future. Try to conclude the email on a positive note.