How to Clear Cache in the Outlook Mobile App

To clear Outlook’s temporary files, first try resetting the affected account inside the Outlook mobile app. On Android, you can also clear the app cache in your phone’s settings. iPhone and iPad do not offer a per-app cache-clearing button, so if resetting the account does not help, you may need to delete and reinstall Outlook. Your email and calendar are usually stored in your account online, but check that messages or drafts have synced before resetting or reinstalling.

What You’ll Need

Your Android phone or iPhone with Outlook installed and an internet connection.
The password and any required verification method for your Microsoft, work, school, or other email account. You may need to sign in again after a reset or reinstall.
A few minutes to let Outlook resync. If you use a work or school account, your organization may require a particular sign-in or device-management process.

Step-by-Step

Check that Outlook has finished syncing. Open the app and look at the Inbox and Outbox. Send any message waiting in the Outbox, and make sure important drafts are saved and visible in the account. If you can, confirm important messages are available in Outlook on the web or another device. A cache reset is intended to remove temporary local information, not mail stored on the server, but unsent or not-yet-synced content deserves extra care.
Try Outlook’s built-in account reset first. In Outlook, tap your profile picture or account icon, then tap the gear icon to open Settings. Select the account that is having trouble. Find and tap Reset Account, then confirm if prompted. Menu wording and placement can vary slightly with app version and account type. If you do not see the option, update Outlook from the Google Play Store or Apple App Store and check again. This reset refreshes the account’s local app data and sync; it is not the same as deleting the account from the email service.
Reopen Outlook and allow it to refresh. Keep the phone connected to Wi-Fi or mobile data and leave the app open for a few minutes. Mail, calendar items, and attachments may take time to download again, especially for a large mailbox. Check whether the original problem is resolved before taking more disruptive steps. If Outlook asks you to authenticate, sign in using the account’s normal method.
If you use Android, clear only Outlook’s cache in the phone settings. Close Outlook, then open the phone’s Settings. Go to Apps (sometimes called Apps & notifications or Application manager), choose Outlook, and tap Storage & cache or Storage. Tap Clear cache. The exact labels vary by Android manufacturer and version. Reopen Outlook and let it resync. Clearing this cache removes temporary files; it should not remove your account from the mail server.
Do not choose Clear storage or Clear data by accident. These options are different from Clear cache. On many Android phones, clearing storage or data resets the app more completely, removes local app information, and may sign you out. Use that only if you deliberately want a broader reset, have confirmed important unsynced content is safe, and can sign in again. If you are unsure which button you are viewing, stop and check your phone maker’s instructions rather than guessing.
If you use an iPhone or iPad, use the in-app reset rather than looking for a cache button. iOS does not provide a general Clear cache control for an individual app in Settings. Start with Outlook’s Reset Account option in the app. If that does not fix the issue, follow the reinstall steps below. The iPhone’s Offload App option keeps an app’s documents and data, so it is not the same as removing the app’s stored data and may not clear the information you are trying to refresh.
As a last resort, remove and reinstall Outlook. First confirm you know your account password and can complete any multifactor authentication. Verify important drafts and unsent messages are synced or save their contents somewhere safe. Delete Outlook from the phone, restart the device if convenient, then install Microsoft Outlook again from the official app store. Open it, add your account, and allow mail and calendar data to download. Do not remove a work or school account if your organization has told you to use a managed installation or contact its support team first.
Check the result before changing other settings. Open the folder, message, or attachment that was causing trouble. If it now loads, the temporary data was likely part of the problem. If it still fails, note any error message and whether the problem happens on Wi-Fi, mobile data, or both; use the troubleshooting section before removing additional accounts or changing phone-wide settings.

Common Mistakes

Confusing cache with account data: On Android, Clear cache and Clear storage or Clear data are separate actions. The latter can reset Outlook more thoroughly and require you to set the account up again. Read the button label carefully before tapping.

Expecting the same controls on every phone: Android manufacturers organize Settings differently, and iOS does not offer the same per-app cache control. Follow the instructions for your operating system rather than searching for an Android-style cache button on an iPhone.

Resetting before checking unsent work: A message still in the Outbox or a draft that has not synchronized may exist only on the device. Check these items first; when possible, verify them in webmail or on another device. Do not assume every piece of app data is backed up just because your mailbox is online.

Removing the account from the provider: You normally do not need to delete the mailbox itself or change its server settings to clear local app files. The goal is to refresh Outlook on the phone, not delete your Microsoft, work, school, Gmail, or other email account.

Closing Outlook too quickly after the reset: The app may need time and a stable connection to rebuild its local view. If you open it briefly and immediately go offline, it can look as though mail has disappeared when it is simply still syncing.

Tips

Use the least disruptive option that matches your phone: try Reset Account first, then Android’s Clear cache if needed, and reserve a reinstall for persistent problems. A reset is not a substitute for checking whether the service is online or whether your account can sign in through a browser.

Keep Outlook updated through the official app store. Updates can fix sync and display issues, and the Settings screens may change between versions. If you are following instructions from a support page, check that they refer to Outlook for iOS or Android rather than Outlook for Windows or Outlook on the web; those products use different menus.

After clearing temporary files, give the app time to download recent mail and calendars. Large attachments may need to be downloaded again when opened. If your phone is low on storage, free up space using the phone’s storage tools; clearing Outlook’s cache may help a little, but it is not a reliable way to recover a large amount of space.

For a managed work or school phone, check with your organization’s IT team before deleting the app or clearing all app data. Company policies can require device enrollment, a specific authentication method, or a managed version of Outlook. Keeping the exact error message and noting what you already tried makes support easier.

Troubleshooting

Reset Account is missing: Confirm you selected the affected account rather than the general settings screen. Update Outlook, close and reopen it, and check the account settings again. If the option is still absent, do not substitute an unfamiliar control; use Android’s system cache option if applicable, or contact your organization’s support team for a managed account.

Outlook asks for a password after the reset: This can be expected because the app may need to authenticate again. Enter the current password and complete the verification prompt. If sign-in fails, test the same account in a browser. If browser sign-in also fails, the problem may be the password, account status, or organization’s sign-in policy rather than the cache. Avoid repeated guesses that could lock the account.

Mail or calendar items seem missing: Make sure the phone is online, reopen Outlook, and wait for synchronization. Check the same mailbox in webmail or another device. If items are absent there too, investigate the account, folder, or service rather than clearing the cache again. Check that Outlook is showing the correct account and folder, and use search if a message may have moved.

The original issue remains after clearing cache: Restart the phone, update Outlook, and check whether the problem occurs on both Wi-Fi and mobile data. Confirm that the phone has free storage and that the email service is available. If only one account is affected, focus on that account’s sign-in or sync status. If the issue affects several accounts, it may be an app, network, or device problem.

You accidentally cleared Android storage or data: Open Outlook and add the account again, then complete sign-in and verification. Allow the mailbox to sync. Check webmail for drafts or messages that are not present on the phone. If you cannot sign in or the account is managed by work or school, contact the account administrator instead of repeatedly deleting and reinstalling the app.

Reinstallation does not help: Check for an Outlook service issue, confirm the device’s date and time are set correctly, and try a different network. Record your Outlook version, phone model, operating-system version, account type, and exact error text. Use Outlook’s in-app Help or your organization’s IT support for account-specific assistance. Do not send anyone your password or verification code.

Frequently Asked Questions

Will clearing Outlook’s cache delete my emails?
Normally, clearing temporary cache does not delete mail stored on the email service. Mail and calendar data should sync back after Outlook reconnects. However, unsent messages or drafts that have not synchronized may be at risk during a broader reset or reinstall, so check them first.

How do I clear the Outlook cache on an iPhone?
There is no general per-app cache-clearing button in iOS Settings. Try Outlook’s Settings > account > Reset Account. If the problem continues, confirm your content is synced and your sign-in details are available, then delete and reinstall Outlook.

Does clearing Outlook’s cache sign me out?
Android’s Clear cache usually leaves account sign-in intact, although Outlook may need to refresh. Reset Account, clearing app storage, or reinstalling can require you to sign in again. Keep your password and required verification method available.

Is Clear Cache the same as Clear Data on Android?
No. Clear cache removes temporary files. Clear data or Clear storage can erase more local app information and reset the app. Choose the cache option only if that is the action you intend.

How often should I clear the Outlook mobile cache?
There is no need to clear it on a schedule. Try a reset or cache clear when Outlook has a specific problem, such as stuck syncing or an attachment that will not refresh. Repeatedly clearing cache is unlikely to solve an account or network problem.

Why is Outlook still using a lot of storage after I clear cache?
The app also uses space for its installation and other local data, and those are not necessarily removed by clearing temporary files. Check your phone’s storage breakdown. On iPhone, removing and reinstalling the app may reduce local app storage, but only do so after checking synced content and confirming you can sign in again.

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