This question came up in a forum discussion recently:
I open, read and reply to an email on my iPhone or iPad. When I open Outlook on my laptop, it doesn't show that the email has been read or replied to. What do I need to do so that my email syncs on all of my devices?
To sync changes to email accounts back to the server you need to use an account type that syncs with the server. IMAP, Exchange server, and Hotmail Connector (plus EAS in Outlook 2013) will sync changes back to the server while POP3 is download only.
You will need to configure all accounts to use the same account type if you want to sync changes between the different email clients; you can't use IMAP on the smartphone and POP3 in Outlook.
Published October 12, 2012. Last updated on October 12, 2012.