How to Clear Cache in the New Outlook Desktop App on Windows

To clear the cache in the new Outlook desktop app on Windows, close Outlook, open Settings > Apps > Installed apps, choose Outlook (new) > Advanced options > Reset, and then reopen the app. This clears local app data that may be stale or damaged; it does not delete messages stored in your online mailbox. Before resetting, make sure drafts and outgoing messages are saved or sent, because anything not synced could be lost.

What You’ll Need

A Windows 10 or Windows 11 computer with the new Outlook app installed. These directions are for Outlook (new), not classic Outlook.
Access to the Windows account that installed or manages the app. If your computer is managed by an employer or school, you may need an administrator for app settings.
Your work, school, or personal account sign-in details, including any required multi-factor authentication method. Resetting can require you to sign in again.
A working internet connection after the reset so Outlook can reconnect and download current mailbox data.

Step-by-Step

Check that you are using new Outlook. Open Outlook and look at the app interface. New Outlook is the newer app and is commonly labelled Outlook (new) in Windows’ installed-app list. Classic Outlook is usually part of Microsoft 365 or Office and has a different desktop interface. If the app has a File tab and you have opened classic Outlook, stop here: these steps do not clear its cache. Do not reset the wrong Outlook listing.
Make sure important work is saved. Open the Outbox and confirm that messages waiting to send are sent or saved as drafts. Check any draft you are editing, and copy its text somewhere safe if it is important. Give Outlook time to finish syncing before proceeding. Mail and calendar information that has already synced to your account is normally stored online, but a reset can remove local app data, including unsynced changes and downloaded offline content.
Close Outlook completely. Close its window and wait a few seconds. If it remains open in the background, right-click the taskbar and open Task Manager, select Outlook if it is listed, and choose End task. Use this only after saving work; ending the task can discard an unsaved message. Closing the app first helps Windows apply the reset cleanly.
Open the installed-app settings. In Windows 11, select Start > Settings > Apps > Installed apps. In Windows 10, use Start > Settings > Apps > Apps & features. You can also search Windows Settings for Installed apps or Apps & features. The precise wording depends on your Windows version.
Find the new Outlook entry. Search or scroll the app list for Outlook (new) or the new Outlook app entry. On Windows 11, select the three-dot menu beside it and choose Advanced options. On Windows 10, select the app entry and choose Advanced options if that option is shown. Make sure the publisher and app identity match the new app, rather than classic Outlook.
Try Repair first if you want the less disruptive option. On the Outlook app’s advanced-options page, choose Repair if available. Repair attempts to fix the app without performing the more thorough data reset. Open Outlook and see whether the issue is gone. If the problem persists, return to the same page and continue with Reset. Repair is optional; it is not the same as clearing the app’s local data.
Reset Outlook. On the advanced-options page, find the Reset section and select Reset. Read the Windows confirmation and select Reset again to confirm. This removes the app’s locally stored data and returns the app to its initial state. It is more comprehensive than Repair, so expect to reconnect accounts and wait while mailbox data loads again.
Reopen Outlook and sign in if prompted. Start the new Outlook app from the Start menu. Follow any sign-in or account setup prompts, complete multi-factor authentication, and allow the app time to synchronize. The first launch after a reset may take longer than usual. Keep the computer online while messages, calendar entries, and other account data repopulate.
Check the original problem. Try the action that was failing, such as opening a message, searching, syncing a folder, or displaying a calendar item. Confirm that recent mail appears and that a test message can send if appropriate. If the issue remains, use the troubleshooting section below rather than repeatedly resetting the app.

What the reset does: It clears local data held by the new Outlook app and can resolve problems caused by a damaged or outdated local app state. It is not a command to erase your online mailbox. Mail and calendar items that are already synchronized with Microsoft 365, Exchange, Outlook.com, or another connected service should return as Outlook reconnects. The reset may remove local preferences, account setup, offline copies, and unsynchronized changes, so treat it as a repair step with consequences—not as a harmless refresh.

Common Mistakes

Resetting classic Outlook by mistake. The Windows app reset applies to the new Outlook app. Classic Outlook has separate profiles and data files; resetting its listing or deleting files using new-Outlook directions is not an appropriate substitute.
Assuming reset deletes mail from the server. It clears local app data, not messages already stored in the connected mailbox. Still, verify that drafts and outgoing mail have synced first, because local-only work may not be recoverable from the server.
Choosing Reset before trying a lighter fix. If Outlook merely needs to reconnect, restarting it or using Repair may be enough. Reset can mean signing in again and waiting for data to download, so use it when basic restart and repair steps have not solved the problem.
Deleting random folders in AppData or WebView2. Avoid removing Outlook, Windows WebView2, or Office folders by hand. Those folders can contain data used by other apps, and deleting the wrong files may create new problems. Use Windows’ supported app settings instead.
Confusing mailbox storage with the app cache. Outlook settings related to mailbox or cloud storage manage messages and attachments in the account; they are not necessarily controls for the desktop app’s local cache. Do not delete mail to try to fix an app-cache issue.

Tips

Restart before resetting. Quit Outlook, restart Windows, and reopen the app. A temporary process or connection issue may clear without removing local app data.
Keep Outlook updated. Check for app updates through the Microsoft Store or your organization’s approved update process. An update can fix a defect that would otherwise return after clearing the cache.
Know what is synchronized. If you can see a message or calendar item in Outlook on the web, it is generally present in the online account. That check is useful before resetting, but it does not guarantee that every unsent draft or local change has synced.
Allow time after the reset. Search results, older messages, and attachments may not be available immediately while Outlook rebuilds its local data. Keep the app open and connected instead of interrupting the initial sync.
Use this as a targeted fix. Clearing the app’s local data is most relevant when the app behaves incorrectly despite a working account and internet connection. It will not fix an expired password, a service outage, or an administrator policy blocking access.

Troubleshooting

Advanced options is missing. Confirm that you selected the new Outlook app and that you are in Windows Settings, not Outlook’s own settings. On Windows 11, use Settings > Apps > Installed apps; on Windows 10, use Settings > Apps > Apps & features. If the app is managed by your organization or the option is unavailable, ask your administrator before attempting removal or another repair method.

Reset is unavailable or does not complete. Close Outlook and try again. Restart Windows, return to the app’s advanced-options page, and check whether Repair is available. If Windows reports an error, note the exact message and contact your IT support team or Microsoft support. Avoid force-deleting app folders as a workaround.

Outlook opens but does not show all mail. Check that the correct account is connected and that the computer has internet access. Give synchronization time, then check Outlook on the web using the same account. If the message appears on the web but not in the desktop app, restart Outlook and check for updates. If it is missing from both, investigate the account, folder, or service rather than clearing the app again.

You cannot sign in after resetting. Verify the username and password, complete any multi-factor prompt, and check whether your organization requires a particular sign-in method or device approval. A reset does not change your account password. If access is blocked or the account is locked, contact the account administrator or service provider.

The problem returns after a reset. The cause may be an app bug, a faulty update, a damaged Windows user profile, an account-side problem, or a network restriction rather than cached data. Record the Outlook version, Windows version, affected account type, and any error text. Check whether the same behavior occurs in Outlook on the web, then share those details with support. Repeated resets are unlikely to help if the underlying issue is outside the app cache.

You are on a Mac. The Windows path through Settings > Apps > Installed apps > Advanced options does not apply to macOS. Quit and reopen Outlook, install available updates, and check whether the issue also occurs in Outlook on the web. Mac versions have different account and folder controls; do not apply Windows file-deletion instructions or manually remove Outlook container files. If a reset or reinstall is required, follow Microsoft’s current Outlook for Mac support instructions or ask your organization’s IT team, especially before removing an account with offline changes.

Frequently Asked Questions

Does clearing the new Outlook cache delete my emails?
No, resetting the app removes local app data, not messages already synchronized to your online mailbox. Unsynced drafts, queued messages, or other local-only changes may be lost, so check them before resetting.

Is Repair the same as Reset?
No. Repair is the less disruptive Windows option and tries to fix the app without a full local-data reset. Reset clears the app’s local data and can require you to sign in and synchronize the account again.

Will I have to add my email account again?
You may be asked to sign in or set up the account again after resetting. Keep your password and any required verification method available. Your account password itself is not changed by the reset.

How long does Outlook take to rebuild its cache?
There is no fixed time. It depends on your connection, mailbox size, and the amount of data Outlook needs to synchronize. Recent mail may appear first; older items and search results can take longer.

Can I clear only one folder’s cache in new Outlook?
The Windows Reset option clears local app data rather than targeting a single folder. Do not use classic Outlook instructions for an individual folder unless you have confirmed they apply to your specific app and version.

Should I clear the cache regularly?
Usually, no. Reset only when troubleshooting suggests a local app-data problem. Routine resets can cost time, remove local preferences, and require account sign-in without preventing unrelated connection or service issues.

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