When changing an existing action that is set to run for a certain number of times (once or n times), the question is what happens on clients where it has already been executed: 

In other words: 

For e.g. an Action set to run "Once only" this means that 


See Also
The When tab
Specifying how often an Action is supposed to run (Repeat interval)
Configuring a maximum number of executions
Selecting one or multiple conditions of which ALL must match for an Action to execute
Selecting one or multiple conditions
Combining the ALL and At least ONE list of Conditions
Selecting one or multiple conditions out of which At least ONE must match for an Action to execute
Restricting an Action to only run for users with a specific home/mail-server