All, We have four Exchange 2000 servers within our organisation. The master server is set up to generate the off line address books for our mobile clients. When a client who's mailbox is on that server downloads the offline Address book things work fine. however, for other clients who are on one of the other exchange servers the address book does not download. when I check the synchronisation log I see the entry 09:48:32 Microsoft Exchange offline address book 09:48:32 0X8004010F Does anyone know how I can fix this? Do we have to replicate the OAB version 2 Public folders to our other servers? Any help or trouble shooting tips would be appreciated thanks Kerman