Hold all email transactions in the old server. You can utilize any exterior relays to retailer your incoming emails till your migration is done. zmprov ca $i CHANGEme cn "$givenName" displayName "$displayName" givenName "$givenName" zmprov ma $i userPassword "$shadowpass" In-Put archives in the resource are dealt with otherwise to straightforward https://www.hostscheap.com/zimbra-migration-service