10000455 
Message
If you remove an Activity, it cannot be restored. Continue?
Diagnosis
While an activity document is displayed, you have chosen the Remove option from one of the following:
The context menu
The Data menu
Procedure
Do one of the following:
To permanently delete the activity, choose Yes.
NoteIf choose Yes, the activity will not appear in reports and will be deleted from the calendar of the user for whom it was assigned.
End of the note.To keep the activity without deleting it, choose No.