Fixed update method
diff --git a/erpnext/crm/doctype/appointment/appointment.py b/erpnext/crm/doctype/appointment/appointment.py
index 219f931..b259758 100644
--- a/erpnext/crm/doctype/appointment/appointment.py
+++ b/erpnext/crm/doctype/appointment/appointment.py
@@ -47,7 +47,7 @@
subject=_('Appointment Confirmation'))
frappe.msgprint('Please check your email to confirm the appointment')
- def on_update():
+ def on_update(self):
# Sync Calednar
cal_event = frappe.get_doc('Event',self.calendar_event)
cal_event.starts_on = self.scheduled_time