I am testing demo GeniusConnect edition 4-2000 Outlook version with an Exchange 2003 mailbox.

Until now we use OutlookConnect edition 2-2000 with an outlook
2K pop mailbox. When the stored item was not existing in the mysql
table, OutlookConnect inserted it and when it was already existing
OutlookConnect updated it.

Now with the demo GeniusConnect 4-2000 edition, the insert operation still working fine, when the contact not exist in the contacts table but when it already exists GeniusConnect fails to insert instead of just update the existing one.

Is there wrong configuration issue or a limitation of the demo version ?

What is the error message?

23000 [MySQL][ODBC 3.51 Driver][mysqld-4.1.9-max]Duplicate entry
'contactLastName-contactFirstName-contactOrganisation' for key 2 (1062)

It obviously true in my case but I'd like GeniusConnect process un UPDATE query instead of an INSERT one in this case.
Are you testing on the same Folder you used with prev.version of GeniusConnect?
Is your primary key 'contactLastName-contactFirstName-contactOrganisation' ?

Can you try to:
-create a new test Contact
-select it in Outlook
-hit "Store Item"
-hit "Load Item"
if the "Load Item" results in "...is not linked to a database record", there is something wrong with your primary key config or GeniusConnect is not able to store the primary key in Outlook item.