There are several actions in the application that might remove the existing messages,
  based on certain conditions. The messages are removed only if they haven't been sent.
Activity Start action
| Event/Action | Description | 
| Removed Messages | Reminder,Change,Day before | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_STARTED | 
Activity Cancelation action
| Event/Action | Description | 
| Removed Messages | All | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_CANCELED | 
Activity Notdone action
| Event/Action | Description | 
| Removed Messages | All | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_NOT_DONE | 
Deletion of a Pending Activity action
| Event/Action | Description | 
| Removed Messages | All | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_DELETED | 
Activity Suspend action
| Event/Action | Description | 
| Removed Messages | Started | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_SUSPENDED | 
Activity Reschedule action
| Event/Action | Description | 
| Removed Messages | All except SLA Warning | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_RESCHEDULED | 
Activity Move action
| Event/Action | Description | 
| Removed Messages | Reminder,Change,Not started,Service window warning,Call ahead,Add | 
| Status | obsolete | 
| Description | ACTIVITY_WAS_MOVED | 
Reminder message creation action
| Event/Action | Description | 
| Removed Messages | Customermessages: Recipient =Customer | 
| Status | obsolete | 
| Description | NEW_CUSTOMER_MESSAGE_WAS_CREATED | 
| Notes | The Reminderlaunch condition is not invoked
if the existing customer messages  cannot be dropped using thedrop_messagecall (if required). | 
Change message creation action
| Event/Action | Description | 
| Removed Messages | Customermessages: Recipient =Customer | 
| Status | obsolete | 
| Description | NEW_CUSTOMER_MESSAGE_WAS_CREATED | 
| Notes | The Changelaunch condition is not invoked
if an incompleteReminderexists, or if the existing
customer messages cannot be dropped using thedrop_messagecall (if required). | 
Cancel visit action
| Event/Action | Description | 
| Removed Messages | All (visit related) | 
| Status | obsolete | 
| Description | VISIT_WAS_CANCELED | 
Delete visit action
| Event/Action | Description | 
| Removed Messages | All (visit related) | 
| Status | obsolete | 
| Description | VISIT_WAS_DELETED | 
Start visit action
| Event/Action | Description | 
| Removed Messages | Visit reminder,Visit change #,Visit day before | 
| Status | obsolete | 
| Description | VISIT_WAS_STARTED | 
Applying new visit formulas action
| Event/Action | Description | 
| Removed Messages | All (visit related) | 
| Status | obsolete | 
| Description | VISIT_WAS_RECALCULATED | 
| Notes | The messages are only removed if the visit is removed as the
result of applying formula changes. | 
Block/Shift messages action
| Event/Action | Description | 
| Removed Messages | N/A | 
| Status | false | 
| Method Description | NONWORKING_DAY | 
| Notes | This removal is performed if message sending of is not allowed
for a non-working day (or a holiday) and such message cannot be shifted
to an appropriate working day. |