Applies ToOutlook for Microsoft 365 Outlook 2024 Outlook 2021 Outlook 2019 Outlook 2016 New Outlook for Windows

In Outlook, you have the flexibility to make Outlook work online or offline with your mail server.

Select a tab option below for the version of Outlook you're using. What version of Outlook do I have?

Note: If the steps under this New Outlook tab don't work, you may not be using new Outlook for Windows yet. Select the Classic Outlook tab and follow those steps instead.

Offline access in the new Outlook for Windows 

You can use the new Outlook for Windows even when you’re not connected to the internet by enabling offline access. When turned on, the new Outlook for Windows saves a copy of your emails, calendar events, and people (previously contacts) to your device, providing access to these items when you're offline and improved performance when you're online. 

Your offline settings determine which items are saved to your device and for how long. To set these, see the section below Update offline settings. When you’re back online, new Outlook for Windows automatically updates the items that were saved to your device. 

Note: For an enterprise user the People app can include company profile information in addition to any details you add or edit for each contact.

What to know before you go offline in new Outlook

You currently need a connection to the internet to open or restart new Outlook. Offline access described in this article is only supported when the app is already running and then goes offline. Opening and restarting the app while offline is planned and will be available in a future update.

What can I do when I’m offline in new Outlook? 

Most actions you perform online are also available when you’re offline. These include, but aren’t limited to:

Read, manage, and view Outlook items: 

  • Read emails

  • Create and save new email drafts 

  • Send new messages to Outbox 

  • Rename folders 

  • View your calendars and events 

  • View your people (previously contacts)  

Perform actions on emails: 

  • Archive

  • Categorize

  • Delete

  • Flag / Unflag Ignore

  • Mark as Read / Unread

  • Move to Focused / Other

  • Move to folder

  • Pin

  • Report Junk / Not Junk

  • Report Phishing

  • Snooze

View and update your settings: 

  • About Outlook

  • Automatic replies

  • Categories

  • Email accounts

  • People view

If you try to do something that’s not available offline, you'll get an error message, or the changes you made will revert back to what was previously saved.

Tip: For a list of what isn't available currently while offline, see the section below Upcoming for offline access.

Update offline settings in new Outlook

Update these settings to choose which folders to save and how many days of items to save. If you have more than one account, select the account you want the settings to apply to:

Select which folders to save locally:

  1. Select Settings > General > Offline > Folders to save.

  2. From the dropdown, select Default (Inbox, sent, drafts, archive, deleted and snoozed), Default and favorites (this is set by default), or Default, favorites, and recently used.

Select the number of days to save emails locally:

  1. Select Settings > General > Offline > Days of email to save.

  2. From the dropdown, select 7 (this is the default value), 30, 90, or 180 days of email to save.

Important: Depending on how much space is available on your device, if your items don’t have enough local storage to save based on your settings, fewer items will be saved, or offline access may be disabled.

Turn offline access on or off in new Outlook

 Offline is turned on by default in new Outlook for Windows. To turn it off or on, do the following:

  1. Select Settings > General > Offline.

  2. Select the toggle Enable offline email, calendar, and people to turn offline access on or off.

  3. Select Save.

What else do I need to know about working offline in new Outlook?

The following aren’t currently available offline, but we plan to include in future updates:  

  • Create, delete, and move folders

  • Reply to and forward emails

  • RSVP to meeting invitations

  • Search for items

  • Sort and filter emails

  • View and add attachments and images

  • View and update settings for notifications, signatures, and calendars

  • View shared and delegated mailboxes

Other capabilities that aren’t available when offline: 

  • View email and calendar groups

  • View favorited people, categories, and search folders

  • Create, update, and delete calendar events and people (previously contacts)

  • View entire global address list

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Switch between working offline and working online in classic Outlook

  • Click Send / Receive > Work Offline.

    Offline command on the ribbon

When Outlook switches between working online and offline in classic Outlook, all email accounts are changed.

You know you’re working offline when Work Offline is highlighted on the ribbon or Working Offline appears on the status bar at the bottom of the classic Outlook window.

Working Offline indicator on the Outlook status bar

When you’re ready to work online again, click Send / Receive > Work Offline. The button text doesn’t change, but it’s only highlighted when you’re working offline. Working Offline on the status bar also goes away when you’re working online.

Change how much mail to keep offline in classic Outlook

  1. Click File > Account Settings > Account Settings.

    Account Settings in the Backstage view

  2. Select an Exchange or Microsoft 365 account, and then click Change.

    Change command in the Account Settings dialog box

  3. Under Offline Settings, move the slider to the desired amount of time, such as All, 12 months, 6 months, 3 months, or 1 month. Note: If you're using Outlook 2016, you can also select an amount of time as short as 3 days.

    Offline mail storage amount slider

    For example, if you move the slider to 3 months, only mail from the past three months will be synchronized to your Offline Outlook Data (.ost) file from the Exchange server. Items older than 3 months reside only in your mailbox on the server. You can change this setting at any time.

    Cached Exchange Mode, which downloads a copy of your messages, must be turned on. If you're using Outlook with an Microsoft 365 account, we recommend you use Cached Exchange Mode.

By default, Outlook configures Exchange and Microsoft 365 accounts to only synchronize 12 months of your email.

Changing the amount of data to synchronize can affect the time it takes Outlook to open as well as the amount of storage space Outlook uses on your computer. If you're running in a virtual desktop environment, we recommend you only synchronize one month of data. 

Status messages in classic Outlook

How do you know when you're working offline or online in Outlook? There are visual cues, starting with the status bar at the bottom of your Outlook window. If either of the following status indicators are shown, it means Outlook isn’t connected to your mail server.

Working offline status or Disconnected status

You can’t send or receive email until you reconnect.

Status: Working Offline

Working offline usually is a choice. Returning to an online work mode is a simple process.

  • In classic Outlook, on the Send/Receive tab, choose Work Offline to reconnect.

    Working offline option on the Send Receive tab

Notes: 

  • If the background of the Work Offline button is shaded (as shown in the image above), you're not connected. But if the background is clear, you are connected.

  • If you don’t see the Work Offline button and your email account is a Microsoft Exchange Server account or a Microsoft 365 account, Cached Exchange Mode might be turned off. Follow the steps in Turn on Cached Exchange Mode to change that setting. Or contact the person who manages the Exchange server for your organization. We recommend always turning on Cached Exchange Mode with a Microsoft 365 account.

Status: Disconnected

There can be different reasons why you're disconnected from classic Outlook. What follows are just a few examples of some of the possible reasons.

  • If your Internet connection is working, there might be a problem with the mail server.

  • If you can log onto your email from a website—for example, http://outlook.com—check to see whether you can receive and send email that way. If email isn’t working on the website, call your technical support for your email service provider for help.

  • If you can send and receive mail on the website, then your mail server is fine. But your computer might need updates or there might be a problem with your account settings.

Tips for reconnecting to classic Outlook

Here are some suggested ways to reconnect to classic Outlook.

Reset the Work Offline status

  • On the Send/Receive tab, choose Work Offline, and check your status bar. If the status shows Working Offline, repeat the action until the status changes to connected.

Notes: 

  • When Outlook is offline, items deleted from Exchange may reappear when Outlook reconnects online. This can happen when (1) server-side an item is hard-deleted and (2) client-side the same item is moved to another folder (including deleted items) during the client’s offline period. When Outlook reconnects online, it resyncs the local copy back into the new folder. In this scenario, the server action is completed successfully. And the client action is also completed successfully. The end user sees this as reappearance of the item. The offline cache is the source of truth for Outlook in this scenario. The resync to the mailbox is expected behavior in this scenario.

  • When running Outlook in cached mode, a similar behavior can occur when conflicting actions are taken on client and server at the same time. Outlook tries to sync up an item move, but the server item has already been deleted so instead of being moved, the item is recreated in the destination folder on the server.

Check for updates

Create a new profile

To eliminate the possibility that there's a fault in your current Outlook profile, create a new profile. If you open classic Outlook using the new profile and it’s still disconnected, try removing your account and then adding it back again.

  1. To remove an email account, follow remove or delete an email account from classic Outlook for Windows

  2. Follow the steps in adding the account again to proceed.

Related articles

Change send and receive settings when working offline in classic Outlook

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