When a task is assigned to one person, you can keep a copy of the task in your Task folder and the person who accepts the task can send you updates. However, this only works when you assign to the task to one person. If the Task is assigned to multiple people, Outlook can't track it and update the status.

In order to track the task and assign it to several people, you need to copy and resend the task.

Follow these steps to assign a task to a multiple people:

1. Assign the task to the first person.
2. Select the Assigned Task and Ctrl+C,V to copy and paste it.
3. Select the copy and assign it to someone else.
4. Repeat as needed.

While this works OK when you need to send the task to a small number of people, it's not workable to send it to a larger group.

To quickly assign a task to multiple people you need to use VBA. In this example, I'm using a userform to ask for the subject, due date and notes field and it's entered into the task.

1. Set macro security to Low
2. Open the VBA editor by press Alt+F11
3. Right click on Project1 and choose Insert > Module
4. Import the userform
5. Paste the following code into the module

Select several contacts and run the macro to test it. Updated September 8 2016 to add an error handler. If contacts are not selected, the macro ends.

Public tSubject, tDate, tNotes As String

Public Sub SendTasksToGroup()
Dim Selection As Selection
Dim obj As ContactItem
Dim objTask As TaskItem
Dim objitem As Object
Set Selection = ActiveExplorer.Selection

Set objitem = Application.ActiveExplorer.Selection.Item(1)
If TypeOf objitem Is ContactItem Then
frmTask.Show
Else
MsgBox "you need to select one or more contacts"
Exit Sub
End If

For Each obj In Selection

 If obj.Class = olContact Then
  Set objTask = Application.CreateItem(olTaskItem)
        With objTask
                .Recipients.Add (obj.Email1Address)
                .Assign
                .Subject = tSubject
                .Body = tNotes
                .DueDate = tDate
                .Display
         End With
  End If
Next

Set objTask = Nothing
Set obj = Nothing
End Sub

If you want to edit the macro directly, you can replace tSubject, tDate, and tNotes with text. In the case of the date, you need to either use .DueDate = Now + 5 (or any whole number) or enter a date in this format: .DueDate = #1/2/2012#