[C4C] preventing contact duplicates

Hi everyone,

we had several cases now where an employee created a new business object and assigned it to a newly created contact (while there is already a contact with same name and last name). When they create the new business object they are asked to assign it to a contact. But instead of checking if there is an existing one the new BO could be assigned to they just create new ones. We would like to have a red alert or notification (or even the option to block creation process) as soon as someone tries to create a contact with a name that already exists.

Any ideas on how to implement this scenario? We have been trying workflows, for example to prompt a notification if someone tries to assign a contact with status = obsolete to a newly created business object. But this does not solve the problem mentioned above where we have to manually delete duplicates from time to time.

I appreciate all kind of help!