Microsoft Copilot Not Working — Fix It Across Browser, App, and Microsoft 365

Overview

“Microsoft Copilot not working” covers a wide range of failures because Microsoft ships Copilot in at least five surfaces: the web app at copilot.microsoft.com, the Windows sidebar, the Edge browser integration, the mobile apps, and the Microsoft 365 suite (Word, Excel, Teams, Outlook). Each surface has its own failure modes, but they share a common authentication and service backbone.

This guide separates the fixes by where Copilot is failing for you. Start with the quick fixes below — they resolve the majority of cases — then move to the platform-specific steps if the problem persists.

Symptoms

What “not working” looks like depends on the surface. Common patterns:

• Blank or spinning response area. You type a prompt, hit send, and nothing comes back — or a spinner runs indefinitely.
• “Something went wrong” error. A generic error banner with no actionable detail.
• Sign-in loop. Copilot repeatedly asks you to sign in, accepts credentials, then redirects back to the sign-in page.
• Feature missing entirely. The Copilot button or icon doesn’t appear in Word, Excel, Teams, or the Windows taskbar.
• “This feature isn’t available” message. Copilot loads but refuses to process your request, sometimes citing your region or account type.
• Partial responses or cutoffs. Copilot starts generating a reply but stops mid-sentence.

If you’re seeing a specific error code (e.g., a numeric HTTP error or a named error string), note it — it narrows the cause significantly during escalation.

Why This Happens

Copilot failures fall into four buckets. Diagnosing which bucket you’re in saves time.

Authentication and session issues. Microsoft’s identity platform (Entra ID for organizations, Microsoft Account for consumers) issues tokens with expiration windows. When a token expires or becomes invalid — after a password change, MFA re-enrollment, or conditional access policy update — Copilot can’t authenticate your requests. This is the most common cause and the easiest to fix.

Plan or license mismatch. Microsoft 365 Copilot requires a specific add-on license assigned by your IT admin. The free Copilot at copilot.microsoft.com has different capabilities and rate limits. If you expect enterprise features but you’re hitting the free tier (or vice versa), Copilot may appear “broken” when it’s actually working as designed for your license.

Regional or rollout restrictions. Microsoft rolls out Copilot features incrementally. A feature available in the US may not be live in your region yet. There’s no universal feature-availability page — you may need to check with your admin or Microsoft’s Copilot documentation for current availability details.

Browser or client-side corruption. Extensions (especially ad blockers, privacy tools, and other AI assistants), corrupted cache, or outdated browser versions can break the Copilot web interface. The Windows sidebar and Office integrations can also fail if the underlying WebView2 runtime is outdated or damaged.

Check Service Status, Account, and Basic Access

Check Microsoft’s status page. Visit status.cloud.microsoft.com and look for incidents affecting Copilot, Microsoft 365, or Entra ID (Azure AD). If there’s an active incident, wait it out — no local troubleshooting will help.

Verify your account type. Sign in at copilot.microsoft.com and check the account icon. Are you signed in with your personal Microsoft account or your work/school account? The two have different Copilot capabilities. If you need Microsoft 365 Copilot features, you must be on a work account with the Copilot license assigned.

Test basic sign-in. Go to office.com or microsoft365.com and confirm you can sign in and access other Microsoft services (Outlook, OneDrive). If those are also broken, the issue is with your account or Microsoft’s auth service, not Copilot specifically.

// If you see 401 or 403 errors in the Network tab when Copilot loads:
✕ 401 Unauthorized — /api/chat/completions
// This confirms an authentication/token problem.
// Fix: clear cookies for *.microsoft.com, sign out, sign back in.

Fix Browser and Web App Issues

If Copilot at copilot.microsoft.com isn’t responding, this section applies.

Step 1: Try incognito. Open a private/incognito window and navigate to copilot.microsoft.com. Sign in fresh. If Copilot works here, the problem is cached data or an extension in your normal browser session.

Step 2: Clear site data. In Chrome: Settings → Privacy and Security → Site Settings → search for “microsoft.com” → Clear data. In Edge: the same path, or press Ctrl + Shift + Delete and select cookies and cached files. Be specific — clear only Microsoft domains to avoid logging out of everything.

Step 3: Disable extensions. Ad blockers (uBlock Origin, AdGuard), privacy extensions (Privacy Badger, DuckDuckGo Privacy Essentials), and other AI assistants can interfere with Copilot’s API calls. Disable all extensions temporarily. If Copilot starts working, re-enable them one at a time to find the conflict.

Step 4: Update your browser. Copilot’s web interface relies on modern JavaScript APIs. Chrome or Edge versions older than a few months may hit compatibility issues. Update to the latest stable release.

Fix Windows Copilot (Sidebar / Taskbar)

The Copilot experience integrated into Windows has its own set of failure modes separate from the web app.

Copilot icon missing from taskbar. Right-click the taskbar → Taskbar settings → confirm the Copilot toggle is enabled. If the toggle doesn’t exist, your Windows version may not have the Copilot integration yet, or your organization’s group policy may have disabled it.

Copilot sidebar opens but shows a blank pane or error.

1. Press Win + I to open Settings, then go to Windows Update and install any pending updates.
2. Check that WebView2 Runtime is installed and up to date. Search “Add or remove programs” for “Microsoft Edge WebView2 Runtime.” If it’s missing, download it from Microsoft’s site.
3. Reset the Copilot app: Settings → Apps → Installed apps → search “Copilot” → Advanced options → Repair. If Repair doesn’t fix it, try Reset (this clears app data).

Copilot works in browser but not in the Windows sidebar. This is almost always a WebView2 or Windows component issue. The sidebar runs a stripped-down browser engine internally. Updating Windows and WebView2 resolves most cases.

Fix Microsoft 365 Copilot in Office Apps

Microsoft 365 Copilot — the one that works inside Word, Excel, PowerPoint, Outlook, and Teams — is a separate product from the free chat. It requires a paid license and has its own prerequisites.

Verify your license. Ask your IT admin to confirm that a Microsoft 365 Copilot license is assigned to your account. You can also check yourself: go to myaccount.microsoft.com → Subscriptions and look for a Copilot entry. No license = no Copilot features in Office apps, regardless of your Microsoft 365 plan.

Update Office. Copilot features require recent builds of Microsoft 365 Apps. Open any Office app → File → Account → Update Options → Update Now. You need to be on the Current Channel or Monthly Enterprise Channel.

Check the Copilot button. In Word or PowerPoint, the Copilot button appears in the Home tab on the ribbon. In Excel, it’s also on the Home tab. If it’s grayed out or missing:
– Confirm you’re signed into the Office app with the account that has the Copilot license (File → Account).
– Check that the file is saved to OneDrive or SharePoint. Copilot in Office apps may not activate for locally saved files.
– AutoSave must be turned on for the document.

Teams Copilot not appearing. In Teams, Copilot features appear in chat, channels, and meeting recaps. If they’re missing, your Teams admin may not have enabled Copilot for your tenant, or you may be on the classic Teams client instead of the new Teams. Switch to “New Teams” if you haven’t already.

Fix Copilot on Mobile

The Copilot mobile app (iOS and Android) is a standalone app separate from the Bing or Edge mobile apps.

Force-quit and relaunch. Swipe the app away from your recent apps list, wait a few seconds, then reopen it. This clears any stuck session state.

Check for app updates. Open the App Store (iOS) or Google Play Store (Android) and search for “Microsoft Copilot.” Install any available updates.

Clear app cache (Android). Settings → Apps → Copilot → Storage → Clear Cache. On iOS, there’s no direct cache-clear option — uninstall and reinstall the app instead.

Check your network. Copilot requires an active internet connection. If you’re on a corporate VPN or a restrictive Wi-Fi network, try switching to mobile data to rule out network filtering.

Sign out and back in. Tap your profile icon in the app → Sign out → Sign back in. This forces a fresh token exchange.

If It Still Fails

If you’ve worked through the steps above and Copilot still isn’t functioning:

1. Capture the exact error. Screenshot any error messages, including error codes. On web, open browser DevTools (F12 → Network tab) and note any failed requests (red entries).
2. Try a completely different device. If Copilot fails on your laptop in Chrome, try your phone or a different computer. This isolates whether the issue is account-wide or device-specific.
3. Check community reports. The Microsoft Answers community and Reddit’s r/MicrosoftCopilot often surface emerging issues faster than official status pages.
4. Contact support. For Microsoft 365 Copilot (enterprise), your IT admin can open a support ticket through the Microsoft 365 admin center. For free Copilot, use the feedback button in the app or visit support.microsoft.com.

The Gotcha Most Guides Skip

Here’s what most troubleshooting articles don’t tell you: Microsoft ships multiple products under the “Copilot” name, and they fail independently. The free Copilot chat can be fully operational while Microsoft 365 Copilot is down for your tenant, or vice versa. The Windows sidebar Copilot can break while the identical experience in your browser works fine — because the sidebar uses a different rendering engine (WebView2) that can be independently outdated or corrupted.

Before you spend an hour troubleshooting, answer one question: which Copilot is actually broken? If you’re not sure, test copilot.microsoft.com in an incognito browser window. If that works, your problem is surface-specific (Windows sidebar, Office app, mobile app), not Copilot-the-service. This distinction cuts your troubleshooting time in half.

The other non-obvious issue: multiple Microsoft account sign-ins. If you have both a personal @outlook.com and a work @company.com account signed into the same browser, Windows session, or Office installation, token conflicts cause unpredictable failures. The fix isn’t just “sign out and sign back in” — it’s using browser profiles or Windows account separation to keep the sessions completely isolated.

FAQ