If you’ve got limited drive space or a slow internet connection, you might want to limit what things Outlook downloads. We’ve shown you how to control the items that Outlook downloads based on the ages of the items, but that’s not very flexible. It also only works on emails in your mailbox (and, for Outlook 2016 and later, delegate mailboxes), so if you’ve got access to public or shared folders, or you’ve got a lot of calendar events and tasks, you need another option. Step forward folder synchronization, which lets you filter the things Outlook downloads on a folder-by-folder basis.
Note: Folder synchronization works with all supported versions of the Outlook client when you are connected to a Microsoft Exchange Server, including Hotmail or Outlook.com. If you connect to another service, like Gmail or a personal mail server, you can configure these options but Outlook may ignore them.
You can access the synchronization options for a folder by clicking Folder > Folder Properties.
You can also right-click the folder in the Navigation pane and then click the “Properties” command.
On the folder’s properties window, switch to the “Synchronization” tab.
The good news is that there’s only one thing to do on this tab: create your filter. Click the “Filter” button to open the Filter window and get started.
The Filter window lets you choose the condition (or conditions) that a message has to meet for Outlook to download it to this folder. Any email that doesn’t meet these conditions still exists on the server, and you can access those emails through the Outlook web app or Outlook online.
Each folder can have different synchronization filters, so if you create a filter on your Inbox, that won’t affect any other folder. You have to create a separate filter for each folder, so it only really makes sense to use this on folders with a lot of items.
Right now my inbox is full of emails where I’ve been CC’ed on stuff that’s not that important, so we’re going to create a filter that only synchronizes mail sent to me and where I’m the only person on the “To” line.
To do this, add a name to the “Sent To” box, enable the “Where I am” checkbox, and then select “the only person on the To line” from the drop-down menu to the right.
Click the “OK” button, and a warning message will appear.
This message means that any emails matching your filter will be downloaded to the folder and any emails that don’t match your filter will be removed from the local folder. The emails that don’t match won’t be deleted—they’ll still be available in the Outlook web app, and if you change or remove your filter, Outlook can download them again.
Click “OK” on the message, and then “OK” on the properties window. Restart Outlook and the filter should be applied immediately, although on folders with thousands of emails it could take some time to re-synchronize. Once your mail filter has synchronized, you can compact your mailbox to maximize the space gain.
To remove the filter, go back to the Filter window and click the “Clear All” button. Close the open windows and restart Outlook to apply the changes.
This synchronization tool is great for shared mailboxes where you only want to see email sent to you or your team. You can also use it to stop showing emails or calendar events that are older than a certain age, filter out large attachments, stop syncing emails from particular addresses, and much more. The filter criteria are many and varied, so if you want to filter particular emails, you should be able to find a combination of filter criteria that lets you do it.