This post is intended to provide some clarifications of this topic and give you troubleshooting tips. If you access your email from different computer or device, it will look like some of your previously downloaded messages have been deleted.Some of the more complicated support calls we see are related to Certificate Based Authentication (CBA) with ActiveSync. To access the email after it's downloaded, you have to use the same computer. Once email is downloaded to your computer, it's deleted from the server. POP email is downloaded from the Exchange Server onto your computer. IMAP allows for limited calendar storage but does not support collaborating on a calendar with other users. With IMAP, email in your Inbox, Deleted Items, Sent Items folders are synchronized between your device and the server. When you read an email message using IMAP, you aren't actually downloading or storing it on your computer instead, you're reading it from the Exchange Server. IMAP, like Exchange ActiveSync, is a method for accessing your email wherever you are, from any device. It allows you to access your email even when you're not connected to the Internet. When you access or read your email, you aren't actually downloading or storing email on your mobile device instead you're reading it from the Exchange Server. Here are the possibilities - ask your business or school how your Exchange account is set up:Įxchange ActiveSync MAPI/HTTP are methods for accessing your Exchange email, usually from a laptop, phone, or tablet. This will determine how your email works. When your business or school sets up their Exchange server, they choose what method your Exchange account uses to access email on the server. Your contacts and calendar are saved there, too. When you use an Exchange account, your email messages are delivered to and saved in your mailbox on the Exchange server.

Microsoft activesync account