Modules & VBA :: Retrieve Outlook Data From Access

It's been some time since I wrote the following, which takes a string made up of "Lastname Firstname Telephone" and writes it at a specific time in Outlook. It uses Late binding so it works across all Oulook versions.

Code:
Public Function funOutputAppointmentToOutlook(dtmDate As Date, strSubject As String)
Dim olApp As Object
Dim mNameSpace As Object
Const olFolderCalendar = 9
Const olAppointmentItem = 1

[Code] ....

I would like to first check the specific Outlook time slot whether the string exists already and only if it does not exist to write it.