Thanks for the replys
i'll had few information
When you sync to a BES server the server is only sending the last 200 emails. So i need to do a backup and a restore to have all my email older than thoses 200. And i wanna keep my other configuration (sounds profile and everything).
And also my new BES server is not using the same database as the previous one. (Moving from one provider to another one)
Thanks again for your help