Outlook Configuration

How to best configure Outlook to access your email

Outlook can be setup in a number of different ways to help you get the best performance from your email, depending on how you work:

I generally use the same computer/laptop

Cached Exchange Mode is best for you, it's also recommended by Microsoft.

This mode takes a copy of your mailbox from the server, copies it to your PC and periodically synchronizes any changes. This makes Outlook much quicker and enables you to still access your mailbox if there's a problem with the network or email server.

Points to note:

Cached Exchange Mode isn't suitable if you regularly use a few different PCs, as every time you log on to a new computer it will try to download your mailbox. If you do need to log on to a different computer, use Outlook Web App to access your email.

Outlook stores your cached mailbox in an file (called a .OST file) that resides in your profile.  For large mailboxes, this file can take up a lot of storage space on your device. To help with this, in Outlook 2013+ Microsoft included a sliding scale of how much you would like to cache.  You can cache a certain amount of recent email and Outlook will make a slower connection to the server for the rest.

Cached Exchange Mode was activated by default when your email moved to Office 365 and when a new Outlook profile is created. 'Download Shared Folders' is also automatically enabled.

Check if you're already using Cached Exchange Mode.

I generally use the same computer but access many (5+) shared calendars and mailboxes

You should use Cached Exchange Mode, but turn off Download Shared Folders.  Outlook sometimes can’t keep up with the synchronization of many different folders and you may find some folders not getting updated.  This is particularly important when managing or accessing frequently updating shared calendars.

How to disable Download Shared Folders

I generally hot-desk

Cached Exchange Mode is not for you, as every time you log on to a new computer it will try and download your mailbox and this can take quite a while. 

The downside to not running Cached Exchange Mode is that navigating your mailbox, searching and sorting your emails will take more time. Outlook is having to make a constant live connection to a server with many other users (potentially thousands) and requests to the server are queued.

Consider using Outlook Web App (OWA), for a much quicker experience, it's more efficient and has most of the functionality of the full Outlook client.