Office 365 Exchange Online
||Authentications are done in plain text, susceptible to main-in-the-middle attack.
||Authentications are over secured channels.
||Duplicate mails when mail client loses information on last email downloaded.
||No duplicate emails, mailbox contents are synchronized with server mailbox.
||Messages sent from PC will not be accessible on mobile device.
||Synchronize your mailbox across multiple connected devices.
||Mailbox sizes are usually small, shared, and with higher costs for bigger disk space.
||50 GB of storage per mailbox ensures minimal issue on mail quota.
||Each device operates separately.
||Flexibility to access your mails & calendar from PC, Mac, web, iPhones, or other mobile devices with similar & familiar view & interface.
||Each additional domain will have additional costs.
||Support for multiple domains for a single fee.
||Individual calendar on each device.
||Access your calendar on the go. All edits & entries are synchronized & similar.
||No option for shared mailbox and calendar.
||Easily share mailboxes and calendars with your colleagues.
||If “leave a copy on the server” is not set, mails are downloaded on client device and deleted from server. In event of disk failure with no backups, all mails will be lost.
||Mails, contacts & calendar entries are retained on both client & server. Failed client systems can resync & recover all mail items prior to failure.
||No control on mail messages once they are downloaded.
||Mail retention policy enables retention of deleted emails, to allow recovery or adhere to corporate policy or regulatory reasons.
||Not available or limited advanced features on other hosted services.
||Advanced messaging features like unified messaging system instant messaging, SSO (single sign on support), hybrid deployment.