1-    We setup their account on our IMAP server
2-    You switch their MX record to point to us (if you give me access I will gladly do it)
3-    You setup the IMAPP account on their local outlook
a.    Drag all folders from the POP to the IMAP account
b.    Messages in POP Inbox, Sent Items, and Drafts will have to be highlighted & dragged to the IMAPP Inbox (outlook will not allow you to drag Inbox)
4-    Login to Webmail & follow the Instruction for “Mobile and Email Client Sync “- when completed this will sync Contacts, Calendar,  Tasks & Folders/Message  already moved to IMAP