How do I update the strEmailsent feild after an email is sent?

VB Code:
  1. DoCmd.SendObject , , acFormatTXT, stEmailAddress3 & ";" & stEmailAddress, stEmailAddress4 & ";" & stEmailAddress2, , stSubject, stText, -1

  2.     rs!strEmailsent = True ' --this is a YES/NO checkbox feild

  3.     rs.MoveNext