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The Outlook setting everyone should check

After setting up Outlook for Windows (classic) maybe your older messages aren’t showing up quickly? That might be because of a hidden default set to suit Microsoft which should be changed to benefit you.

For most mailboxes (, Exchange Server etc) Outlook for Windows (classic) can synchronize a copy of some or all your messages, calendar, contacts etc.  In other words, your info is on a cloud/server plus a clone saved on your computer.  That’s a good thing because the local copy is faster to access and works even if there’s no Internet connection.

That’s called ‘Cached Exchange Mode’ and has been available between Outlook for Windows (classic) and Microsoft serviced mailboxes for many years.  However the default setting has changed and the option to change it not shown during the initial account setup.

Download all email to your computer

When you setup an Exchange Server or account, the latest Outlook for Windows (classic) doesn’t give you any options.  Hidden away is the setting which only downloads the last year of messages.

Go to File | Info | Account Settings | Account Settings | Email tab | choose the account then Change.  You’ll see the Offline Setting, probably with the default one-year (or less) setting.

That’s OK if you have limited disk space but most people don’t have that problem.  They’d be better off caching everything to offline/local storage by moving that slider to ‘All’.

After all, the disk space used by even a large mailbox is relatively low (when drives are measured in Terabytes).  The benefits of a fully cached Outlook far outweighs the disk space used. Modern Outlook and computers can handle VERY large offline storage, so that’s no longer a concern.

Outlook runs slower when older messages are only saved online because the software has to connect to the mail server for data instead of quickly grabbing it locally.

We also like a fully cached Outlook mailbox because it’s a form of backup. If something catastrophic happens to the mail server, you have a full copy of everything on your own computer.

Change Cached Exchange Mode

To get the most from Cached Exchange Mode, go to File | Info | Account Settings | Account Settings | Email then choose the Exchange Server/Microsoft 365/ mailbox. Then choose ‘Change’ for that mailbox.

This option should be ON – ‘Use Cached Exchange Mode to download email to an Outlook data file’

Move the slider to the extreme right ‘All’.

If the device has limited disk space, move the slider to the left (options for years or six, three or one month, weeks or even days).  You’ll save disk space but rely more on an Internet connection.

Why the short default caching age?

This is a good example of a choice made by Microsoft more for their benefit than the customers.

Microsoft’s Surface machines come with relatively small drives, unless you pop for the very expensive options.  The company doesn’t want complaints from those customers about Outlook taking up ‘too much’ disk space, so they reduce the default offline storage for everyone.

The company is obsessed with reducing the number of choices for customers. Over time they have simplified the account setup process and in many ways that’s a good thing with automatic setup by domain name being a godsend.

In our view Outlook’s account setup has been oversimplified with the Cached Exchange Mode being hidden away.

Redmond also wants to push cloud services and this is a way to increase reliance on their services.

What about Send/Receive Groups?

Back in the old days, it was possible to control what was synchronised between Outlook for Windows and the cloud-storage mailbox.  Those options were at Send & Receive groups ….  Each folder could be selected as synchronised or not. Those options are still there but now aren’t the only setting that controls what’s saved on your computer.

Send / Receive | Send/Receive Groups | Define Send/Receive Groups

Group Name ‘All Accounts’ then Edit ….

There’s a separate and unseen Offline Setting which controls the age of messages saved offline.  It’s not mentioned, let alone linked on the Send/Receive settings dialog even though it has a direct impact.

Outlook (new) for Windows – nothing

The new Outlook for Windows has NO offline cache at all. An Internet connection is required for any regular use of this software.

Microsoft has made vague noises about ‘offline support’ in the future but no details or timeline. We can only hope for proper offline caching, similar to what Outlook classic has now … but it’s likely that Microsoft will fob their customers off with something less. Fingers crossed.

Outlook for Mac … sorry

Outlook for Windows (classic) has Cached Exchange Mode but not Outlook for Mac.

That’s a real shame because many Macbooks have limited disk space and could really use a way to reduce the Outlook footprint.

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