Dear Jaya,
the user parameter with value 9 (not 5) just helps you and us to get detailed error message type and number (like CRM_ACTIVITY_SCHED 035). If you have set this user parameter you can always see the message id and type by hover with the mouse over the log. So it is independent of activity scheduling / visit plan.
If you still face an error, I recommend to search first of all for notes (according to your support package) with component crm-btx-act-acs and crm-btx-tou, as there were lot of coding corrections in this aera.
Good luck
Best regards
Rene