Clear Cache in the New Outlook App on Windows

To clear the cache in the new Outlook app for Windows, close Outlook, then use Windows Settings to repair the app first; if that does not help, use the app’s Reset option. Repair is the gentler step, while Reset clears locally stored app data and may require you to sign in again. Your mailbox is normally stored online, but check that important messages have finished syncing before you reset.

New Outlook does not offer a single, universal “Clear cache” button in its settings. The supported Windows repair and reset controls are the most practical way to refresh its local app data when Outlook is slow, displaying stale information, or failing to load correctly. The steps below are for the new Outlook app, not classic Outlook for Windows.

What You’ll Need

A Windows 10 or Windows 11 PC with the new Outlook app installed.
Access to Windows Settings and permission to manage apps. On a work or school computer, your administrator may restrict these options.
Your Microsoft, work, or school account sign-in details, especially if you may need to reset the app and sign in again.
An internet connection and a few minutes for Outlook to resync messages, calendars, and account data after the repair or reset.

Step-by-Step

Confirm that you are using new Outlook. Open Outlook and look at the app interface. New Outlook is the redesigned Windows app; classic Outlook has the traditional desktop ribbon and is usually identified as Outlook (classic) in Windows. The Windows app-reset steps in this guide apply to new Outlook. Do not use classic Outlook instructions for deleting an OST file or clearing its RoamCache folder; those are different applications and data stores.
Check that your mailbox has synced. Connect to the internet and open your Inbox, Sent Items, and any folders containing recent work. Make sure messages you recently sent or drafted have appeared where expected. If you use a shared mailbox or a folder that is still loading, allow it to finish before proceeding. Most Microsoft 365, Outlook.com, Exchange, and IMAP mail remains on the mail server, but unsent drafts or changes that have not synced could be at risk when local app data is reset.
Close Outlook completely. Save any draft you are editing, then close the app using its close button. If it appears to remain open, right-click its icon on the taskbar and choose Close all windows, if that option appears. Avoid resetting the app while a message is being composed or an attachment is uploading. You can also restart Windows if Outlook will not close normally.
Open the app’s advanced options in Windows. In Windows 11, select Start > Settings > Apps > Installed apps. Find Outlook (new) in the list, select the three-dot menu beside it, and choose Advanced options. Depending on the Windows build, the app may appear as Outlook. In Windows 10, go to Start > Settings > Apps > Apps & features, select Outlook or Outlook (new), then choose Advanced options. If your Windows version does not show Advanced options, install available Windows updates or check whether your administrator manages the app.
Try Repair before Reset. In Outlook’s Advanced options, select Repair and wait for Windows to finish. Repair attempts to fix the app without intentionally deleting its app data. It may take a short time, and Windows may not show a detailed progress message. When the process is complete, open Outlook, wait for it to load, and check whether the original issue has gone away. If Repair is unavailable, skip to the reset step only if you are ready to sign in again.
Use Reset if Repair did not solve the problem. Return to the same Advanced options screen and select Reset. Read the Windows confirmation prompt and confirm only if you understand that the app’s local data and preferences can be removed. Reset is more thorough than Repair and is the closest built-in equivalent to clearing the new Outlook app’s local cache. It does not mean that Microsoft deletes your online mailbox, but you may need to add or sign in to your account again, restore preferences, and wait for content to download.
Launch Outlook and sign in if prompted. Open the app from the Start menu. If Outlook asks, enter the email address and password for the account, then complete any multifactor authentication or organization sign-in steps. If you have multiple accounts, confirm that each expected account is present. Follow prompts to allow syncing or offline access if those options appear. Keep the app open and connected while it reloads your mailbox.
Let Outlook rebuild its local data. The first launch after a reset can look slower than usual because the app is downloading messages and rebuilding local information. Open your Inbox and give it time to populate before judging whether it is still stuck. Check recent mail, calendar entries, and any other relevant folders. If you previously used offline access, review the offline settings and turn that feature back on if you need it. The exact settings available can vary by Outlook release and account type.
Check that the original issue is resolved. Test the action that prompted the cleanup: for example, open a message that appeared outdated, search for a recent email, or check whether a calendar item displays correctly. Send a brief test message only if appropriate for your account. If the same error returns after the app has fully synced, the cause may be the account, network, add-in or service rather than cached data; use the troubleshooting section before repeating Reset.

Common Mistakes

Resetting before checking sync: A reset clears local app data, so unsynced work is the main thing to protect. Verify drafts and recent sent items online where possible before continuing. If Outlook is offline, reconnect and wait for pending changes to sync rather than resetting immediately.
Choosing Reset when Repair is enough: Repair is less disruptive and should be the first attempt. Reset can remove local preferences and account setup, so reserve it for persistent problems or when Microsoft support specifically recommends it.
Deleting files from the wrong Outlook folder: Instructions that tell you to remove files from RoamCache or delete an OST file generally refer to classic Outlook. Do not apply those steps to new Outlook or remove files from its app-package or WebView folders by hand. Manual deletion can affect app sign-in, other Microsoft apps, or local data.
Expecting a reset to fix every Outlook problem: Clearing local data cannot repair a mailbox outage, a blocked account, an incorrect password, a full mailbox, or a network problem. If the issue occurs in Outlook on the web too, investigate the account or service rather than repeatedly resetting the app.
Closing Outlook before a draft is saved: Save or send messages first. A draft visible only in the app may not have reached the server yet, particularly if the connection is interrupted.
Assuming the app has failed because it is slow immediately afterward: After reset, Outlook must sign in and resync. Give it time on a reliable connection before interrupting setup or resetting a second time.

Tips

Use Repair as routine maintenance only when there is a symptom. There is generally no need to clear Outlook’s cache on a schedule. Local data helps the app display content efficiently; resetting it pre-emptively adds sign-in and resync work without necessarily improving performance.
Record account details before a reset. Note which accounts are set up and make sure you can access the relevant passwords, authentication app, or recovery method. Work and school accounts may require your organization’s approval or device-management sign-in.
Try a simple restart first. If Outlook has just become unresponsive, close it and restart the PC before using Advanced options. A temporary app or Windows process issue may clear without changing app data.
Keep Windows and Outlook updated. Updates can correct app defects that resemble cache problems. Check Start > Settings > Windows Update for Windows updates. Outlook updates are often delivered through the Microsoft Store or Windows update channels, depending on how the app was installed and managed.
Distinguish an offline cache from online mailbox content. New Outlook may offer offline-related settings, depending on the version and account. Turning offline access off can affect what is available without a connection; it is not a reliable substitute for the Windows Repair or Reset controls when the app’s local data is corrupted.
Use Outlook on the web as a comparison. Sign in through your organization’s approved Outlook web address or Outlook.com. If the same message, search, or calendar issue appears there, it is less likely to be caused solely by the Windows app’s local cache.

Troubleshooting

Outlook is missing from Installed apps. Search the Start menu for Outlook and confirm that the new app is installed. If it is installed but not listed under the expected name, look for both “Outlook” and “Outlook (new).” On a managed PC, contact your IT administrator if Windows hides app controls or blocks Repair and Reset.

Advanced options or Reset is unavailable. Make sure you selected the Outlook app entry rather than a shortcut or a different Outlook component. Update Windows and try again. If the button remains unavailable, do not try to reproduce a reset by deleting random folders; ask your administrator or use Microsoft’s current support guidance for your specific installation.

Repair finishes but the problem remains. Restart Windows, reopen Outlook, and test again. If the issue is still present and you have confirmed that important changes are synced, use Reset. If the problem affects only one account, remove and re-add that account only if the account settings allow it and you know how to authenticate again.

Outlook asks you to sign in repeatedly. Check that the PC has a stable internet connection and that the Windows date and time are correct. Complete any organization security prompts. If sign-in works in a browser but not in the app, update Outlook and Windows; for a work or school account, contact your IT help desk rather than deleting shared Windows credentials or WebView data yourself.

Messages or folders do not appear after reset. Leave Outlook open and online while it syncs, then refresh the folder or restart the app once. Check the same mailbox in Outlook on the web to see whether the messages exist on the server. If they are missing there too, check Deleted Items, archive folders, retention policies, and account status, or ask the mail administrator for help.

The issue returns after the cache rebuilds. Note the exact error, when it occurs, and whether it affects one account or all accounts. Test another network if permitted, check whether Outlook on the web has the same problem, and check for a service notice from your organization or Microsoft. Repeated resets are unlikely to help if the underlying cause is a server, account, policy, or network issue.

Frequently Asked Questions

Is there a Clear Cache button in new Outlook?
There is not a single cache-clearing button available in every version of new Outlook for Windows. Windows’ Repair and Reset options are the practical built-in controls for repairing or clearing local app data.

Will resetting new Outlook delete my emails?
A reset clears local app data, not normally the mailbox stored on the mail server. Your synced mail should return after you sign in, but protect unsent drafts and changes that have not synced before resetting.

Should I use Repair or Reset first?
Try Repair first because it is designed to fix the app without intentionally removing its data. Use Reset if Repair does not resolve the problem and you are prepared to sign in and set up the app again.

How long does Outlook take to reload after a reset?
It depends on your connection, mailbox size, and account type. The app may open before all folders and messages have finished syncing, so keep it connected and allow the initial download to complete.

Do these steps work for classic Outlook?
No. They are for the new Outlook Windows app. Classic Outlook has different cache and profile management, so use instructions specifically written for classic Outlook rather than deleting its files based on this guide.

Can I clear the cache without signing in again?
Repair may resolve an app problem without requiring you to set up the account again, but it does not guarantee that. Reset can remove local app data and may require a fresh sign-in, so have your credentials and verification method ready.

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