thx for your answer, Peter;
i was writing an update of this situation …
actually, i've changed the parameters; i've commented-out 'disable-networking' in MySQL and used a tcp port, and have put a 'bind-address=127.0.0.1' clause to keep my server secure.
I was using the “named pipe” 'cause our clients when they have a firewall, it block the communication port of mysql, so no more connexion to the data base is possible; then the software is not working… and the client complain … 😡 . The named pipe was used cause it doesn't use any communication port …
Anyway, with the bind-address, the sync job works well; but i have to find a solution to avoid the firewall… or to add a rule on every well knwon firewall…. but it's an other task…