Clear Cache in Outlook OWA: Browser Data and Fixes

To clear the cache in Outlook on the web (OWA), clear the cached files in the browser you use to open Outlook, then reload the page. OWA does not have a separate button to empty its browser cache. Start by removing cached images and files; delete Outlook cookies or site data only if a normal refresh does not fix the problem, because that can sign you out.

These steps apply to Outlook in a desktop browser, such as Microsoft Edge or Google Chrome. They can help with a page that will not load, outdated messages or interface elements, or an Outlook tab that behaves incorrectly. Clearing browser cache does not delete messages, contacts, or calendar items stored in your Microsoft 365 mailbox.

What You’ll Need

A current web browser and an internet connection.
Your Microsoft 365 or Outlook sign-in details, in case clearing site data signs you out.
A moment to make sure any message you are composing has saved as a draft. If it has not, copy the text somewhere safe before clearing data or closing the tab.

Step-by-Step

Confirm you are using Outlook on the web. Open Outlook in a browser, usually at https://outlook.office.com, or use the Outlook link provided by your organization. These instructions are for the browser version, not the Outlook desktop app for Windows or Mac. Clearing the browser cache will not clear the desktop app’s separate local data.
Save work and note your browser. Wait for a draft to show that it has saved, or copy its contents before proceeding. Identify whether the Outlook tab is in Edge, Chrome, Firefox, or Safari; use that browser’s settings rather than changing settings inside Outlook. If you use several browsers, clear the data in the one where the problem occurs.
Try a simple reload first. Return to the Outlook tab and reload it. On Windows, press Ctrl+R; on Mac, press Command+R. If the page appears unchanged, try a hard refresh: Ctrl+F5 in Edge or Chrome on Windows, or Command+Shift+R in many Mac browsers. A hard refresh asks the browser to fetch page resources again, but it does not remove saved cookies or all stored site data.
Open the browser’s clear-data controls. In Microsoft Edge, select Settings and more (the three-dot menu) > Settings > Privacy, search, and services > Clear browsing data > Choose what to clear. In Chrome, select the three-dot menu > Settings > Privacy and security > Delete browsing data. Browser labels can shift slightly between versions, so use the settings search box for “clear browsing data” if needed.
Select only cached files to start. In the time-range menu, choose a suitable period; selecting All time clears cached files from the full period. Check Cached images and files in Edge, or Cached images and files in Chrome. Leave cookies and other site data, passwords, autofill data, and browsing history unchecked unless you specifically intend to remove them. Select Clear now in Edge or Delete data in Chrome.
Clear the cache in another browser if necessary. In Firefox, open the menu > Settings > Privacy & Security, find Cookies and Site Data, select Clear Data, and clear Temporary cached files and pages. If the dialog offers cookies as a separate option, leave it unchecked for a cache-only attempt. In Safari on Mac, choose Safari > Settings > Privacy > Manage Website Data; for a targeted cleanup, search for Outlook-related entries and remove only the relevant entry. Safari’s site-data controls may remove more than cached files, so expect to sign in again if you remove Outlook data.
Close and reopen the Outlook tab. After the browser finishes clearing data, close the Outlook tab, open a new tab, and go to your usual Outlook address. Sign in if prompted. The first page load may take longer because the browser needs to download files again.
Check whether the issue is resolved. Open the folder or message that was affected, then test the feature that was failing. For example, if the reading pane looked stale, open a message and then return to the inbox. If the problem continues, try clearing Outlook’s site data specifically, as described below, rather than repeatedly deleting all browser data.
Remove Outlook site data only as a targeted next step. Use the browser’s settings to find stored data for the Outlook website you use, such as outlook.office.com or your organization’s Outlook web address. Remove the matching Outlook entry, then reload and sign in. Avoid deleting every Microsoft or work-account entry unless your organization’s support team recommends it; sign-in can involve more than one Microsoft domain, and a broad deletion may log you out of other services too.

Common Mistakes

Clearing cookies when you only need a cache refresh. Cached images and files are usually the least disruptive place to start. Cookies and site data can contain sign-in state and preferences, so removing them commonly requires you to authenticate again.
Assuming this clears Outlook’s mailbox. Browser cache is temporary local data, not the contents of your Exchange or Outlook mailbox. Do not delete messages or empty Deleted Items as a cache-clearing method.
Clearing data in the wrong browser or profile. A browser can have separate profiles for work and personal accounts. If Outlook is open in a work profile, clearing the personal profile’s cache will not affect that Outlook session.
Closing Outlook before a draft has saved. Most drafts sync automatically, but a connection problem can delay saving. Check for a saved status or copy important text before clearing site data, signing out, or closing the tab.
Expecting every problem to be caused by cache. An outage, account restriction, browser extension, network filter, or damaged profile can produce similar symptoms. If a clean cache makes no difference, test the browser and account before repeating the same cleanup.

Tips

Use a private window as a quick comparison. Open an InPrivate window in Edge or an Incognito window in Chrome, then sign in to Outlook. If Outlook works there but not in your regular window, an extension, profile setting, or stored site data may be involved. Private browsing is a diagnostic test, not a permanent fix, and your organization may restrict it.
Keep the cleanup narrow. Clear cached files first. If the issue affects only Outlook, remove only Outlook’s site data where your browser supports that option. This avoids signing out of unrelated websites and deleting useful browser settings.
Allow for a slower first visit. After clearing cached files, Outlook has to download some resources again. A brief delay on the next load is normal; it should not require deleting additional data.
Use your organization’s approved sign-in route. Work accounts can use a custom Outlook URL, single sign-on, or additional security checks. Bookmark the official address supplied by your organization rather than relying on a link from an unexpected email.

Troubleshooting

Outlook still shows a blank page or loading spinner: Check your internet connection, then try Outlook in a private window or a second supported browser. If it works in the second browser, disable browser extensions temporarily in the affected profile, especially content blockers or script-blocking tools, and reload. Re-enable extensions one at a time to identify a conflict. If Outlook fails in multiple browsers, check your organization’s service-status notices or contact its IT support team.

You are repeatedly asked to sign in: Clearing cookies or site data can remove the session that keeps you signed in. Sign in through your normal work or school account page and complete any multifactor authentication prompt. If the sign-in loop continues, check that cookies are allowed for the required Microsoft sign-in and Outlook sites, and check whether your browser blocks third-party cookies or your organization uses a managed sign-in policy. Do not weaken company security settings without approval; ask IT for the correct browser configuration.

Messages or folders still look out of date: Confirm that Outlook is online and that the same changes appear when you open the mailbox on another device or browser. A message that has not finished sending or syncing may not yet be present on the server. Refresh Outlook after confirming the connection, and check the Outbox or Drafts folder. Cache clearing cannot force an unsent message to sync.

The browser does not show the menu names listed above: Browser settings vary by operating system and release. Use the settings search field for terms such as cached images, clear browsing data, or site data. On Mac, use the browser’s Mac menu and settings rather than Windows keyboard shortcuts; the reload shortcut is usually Command+R. If a managed browser hides or locks a setting, contact your administrator instead of trying to bypass the policy.

You meant the Outlook desktop app: These steps clear data held by a web browser and apply only to Outlook in a browser. The classic Outlook for Windows desktop app has different troubleshooting options, and the new Outlook app also manages local data separately. Do not remove Outlook desktop profiles or app data using these browser steps; use the repair or support guidance for the specific desktop version.

Frequently Asked Questions

Will clearing the OWA cache delete my emails?
No. Clearing cached browser files does not delete mail stored in your mailbox. Removing Outlook site data can sign you out or reset local website preferences, but it is not a mailbox deletion command.

Does Outlook on the web have a clear-cache button?
No separate OWA button clears the browser cache. Use your browser’s cache controls. For a problem limited to Outlook, remove only its site data if clearing cached files and reloading do not help.

Should I clear cookies as well as cached files?
Not at first. Clear cached images and files, then reopen Outlook. Clear cookies or Outlook site data only if the problem persists or you need to reset a broken sign-in session, and be prepared to sign in again.

How often should I clear the Outlook web cache?
There is no need to clear it on a schedule. Browsers manage cached files automatically. Clear them when troubleshooting a specific loading, display, or stale-content problem, rather than as routine maintenance.

Will this fix Outlook not syncing?
It may help if the browser is displaying stale content, but it will not fix an account, network, service, or unsent-message problem. Check the connection and Outbox, compare with another browser, and contact your organization’s support team if the mailbox still does not sync.

Try it: the Date Difference Calculator: days, months, years and weekdays between two dates, with the DATEDIF formulas.

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