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Office 365 – The Exchange Online “Clutter” Feature: Did You Know?

It’s been about 18 months since Microsoft announced the “Clutter” feature in Exchange Online. In that time, the default nature of Clutter has changed and it seems that many either love or hate the feature.
I recently had to dig into the details around “Clutter” for a client as some of the specifics around the behavior of the feature are not well documented.
Below are a few things you may not have known…

Quick Overview

The idea of the Clutter feature is to take “low-priority” emails and automatically move them out of your inbox into another folder. The thought is if there is a particular type of email you rarely read, but isn’t junk/spam, the message will be filed away into a folder where you can review it later. In order to achieve this goal, Exchange Online needs to be able to watch your behavior for a period of time before it can be “trained” on what to identify as clutter.

What Is / Isn’t Considered “Clutter”?

There are some emails that will never be identified as clutter. Some of these include:

  • Messages where you are the sender
  • Messages from anyone in your management chain
  • Messages from your direct reports

Based on these items, you may find additional reason to populate org information in Active Directory if you’re not doing so today.

Is It Enabled?

When the feature was initially released, it was “opt-in” in that you had to explicitly enable it on a per-mailbox basis. Microsoft has since made a change so that Clutter is now enabled by default for all mailboxes. There are, however, some reasons why you may not see Clutter enabled instantly on a mailbox.
The Clutter feature will be automatically enabled after the user has received roughly 1,000 emails. My experience is that it is not instantly at 1,000 messages but can take a week or two before it is enabled. When enabled, the user will receive a “What is Clutter?” email in their “Clutter” folder welcoming them to the feature; the email also contains a link to the options page that allows the user to disable the feature.

Another reason you may find that Clutter is never enabled is if you have disabled OWA for a user. Since the Clutter feature is managed in OWA, Microsoft will not enable it if the user does not have access to the management interface.

How Can It Be Disabled?

Users can disable Clutter themselves via “Options” within OWA. Otherwise, administrators can disable Clutter via PowerShell with the “Set-Clutter” cmdlet. For organizations that want to disable the feature across their entire tenant, there is unfortunately not a single setting to make this change; each mailbox will need to have “Set-Clutter” run against it.

Controlling “Clutter” Behavior

The Clutter feature is intended to be managed by the user in that they can “train” it by moving messages in or out of the “Clutter” folder. You can either drag emails between folder or use the “Move to Clutter” option in Outlook and OWA to help with the sorting logic.
Administrators can block emails from being filed as clutter through the use of an Exchange Transport Rule that sets the “X-MS-Exchange-Organization-BypassClutter” header.

PowerShell Nuances

As mentioned above, Clutter is automatically enabled after certain behavior metrics are met. When a mailbox is first migrated or provisioned in Office 365, the “Get-Clutter” cmdlet will show “IsEnabled” as “False”. Once a user reaches the metrics for being enabled, “IsEnabled” logically changes to “True”.
Unfortunately, there seems to be nothing exposed to admins that shows the difference between a user that has not yet met the metrics vs a user that has explicitly had Clutter disabled. So if you have a new mailbox that you want to have Clutter disabled on, you need to run “Set-Clutter” and set “IsEnabled” to “False” even if it’s already set to that value.
This is something that is a bit confusing and I would like to see updated.

Personal Notes

I’ve had some clients that specifically state they do not want Clutter enabled for their users; others allow the feature to be used as Microsoft intends in that they leave it up to the user to follow the prompts and disable if they choose so. Personally, I have Clutter enabled on both my work and personal mailbox. My work mailbox receives very little into the Clutter folder, mostly notifications from Yammer. My personal mailbox, however, does a pretty good job of sorting bulk mailings such as sale notifications or other items that might be of interest to me but I probably don’t make a priority to read.
Could Clutter result in a user missing an email? It could, especially if the user is a heavy mobile user. The word “missing” here probably needs some definition as the email is obviously still in the mailbox, just in the “Clutter” folder as opposed to the inbox. Additionally, as Clutter catches new emails, it will place a message in the inbox stating what new types of emails were filed away.
Email usage is something that is very individual for each person. You have the “pilers” with thousands of messages in their inbox and the “filers” with hundreds of folders. Everyone uses it differently and “Clutter” is just another option that will appeal to some but not all users.
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Thoughts on “Office 365 – The Exchange Online “Clutter” Feature: Did You Know?”

  1. David Margossian

    Joe, Great update on Clutter and its current behavior. If I may add, we’ve taken the next step and created a Retention Policy/Tag for the Clutter folder. Its one of the few that allow the Retention Policy to have a separate tag. We set retention as 90 days on the Clutter folder and then remove. The thought being if someone hasn’t read or searched for something in 90 days, it can be removed. As you wrote, a very personal choice but for all but I’ve come to appreciate how much it removes from my Inbox.
    Another major benefit is how much important mail I do not miss in my mobile device as it is uncluttered now. – David

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