If you use Teams on the web and see a red error icon next to your message, chat delivery is failing. This usually happens because of a network interruption, an expired sign-in token, or a browser cache conflict. The message is stuck in a pending state and may not reach the recipient at all. This article explains why delivery fails and gives you a step-by-step fix to get your chat working again.
You will learn how to resend failed messages, clear the browser cache, and check your network connection. You will also see how to switch to the desktop app if the web client keeps failing. The fixes below work in Microsoft Edge, Google Chrome, and Mozilla Firefox.
Key Takeaways: Fix Chat Delivery Failures in Teams on the Web
- Right-click the failed message > Resend: Retries delivery of a stuck message without retyping it.
- Ctrl+Shift+R (hard refresh): Forces the browser to reload Teams and clears temporary glitches.
- Teams admin center > Org-wide settings > External access: Confirms external chat is allowed for your tenant.
Why Teams on the Web Fails to Deliver Chat Messages
Teams on the web is a full client that runs inside your browser. It uses the same service as the desktop app, but it depends on the browser’s network stack and storage. When delivery fails, the message is stuck in the outbox. The most common causes are an unstable internet connection, an expired authentication token, or a corrupted browser cache.
A second cause is a mismatch between the web client and the Teams service. If your browser blocks third-party cookies, the sign-in token cannot refresh automatically. When the token expires, Teams cannot confirm that you are still authenticated, so it rejects the message. A third cause is an external access policy. If the recipient is outside your organization and external chat is disabled, delivery fails with a red icon.
The Role of the Browser Cache
The cache stores parts of the Teams web app. If the cache is outdated or corrupted, the client may send malformed requests. The service then responds with an error, and the message stays in the pending state. Clearing the cache forces a fresh download of the app files.
Network Timeouts and Proxy Settings
A proxy or firewall can block the WebSocket connection that Teams uses for real-time chat. If the connection drops for more than a few seconds, the client marks the message as failed. Corporate networks with strict security filters are a frequent source of this problem.
Steps to Resend Failed Messages and Clear the Browser Cache
Follow these steps in order. Test after each step to see if the message sends. Do not skip the cache clearing step. It resolves most delivery failures.
- Resend the failed message
Right-click the message that shows the red error icon. Select Resend from the menu. If the option is not available, copy the message text, delete the failed message, and paste it into a new message. - Hard refresh the browser
Press Ctrl+Shift+R on Windows or Cmd+Shift+R on Mac. This reloads Teams from the server and discards the cached version of the page. Wait for the app to fully load, then try sending a test message. - Clear the browser cache for Teams
Open your browser settings. In Edge or Chrome, go to Settings > Privacy and security > Clear browsing data. Select Cached images and files and Cookies and other site data. Choose All time as the time range. Click Clear data. In Firefox, go to Settings > Privacy & Security > Cookies and Site Data > Clear Data. - Sign out and sign back in to Teams
Click your profile picture in the top right of Teams. Select Sign out. Close the browser tab. Reopen Teams on the web and sign in with your work account. This refreshes your authentication token. - Check your network connection
Open a new browser tab and go to a simple website like example.com. If the site loads slowly or fails, your internet connection is the problem. Restart your router or switch to a wired connection. Then try sending the message again. - Disable any VPN or proxy temporarily
If you use a corporate VPN, disconnect it and try sending a message. If the message goes through, the VPN is blocking the WebSocket connection. Contact your IT team to allow the Teams domain and all subdomains through the proxy.
Related Failures and How to Fix Them
Teams Shows a Red Circle With an Exclamation Mark
This icon appears next to the chat list, not on a single message. It means the entire chat channel is disconnected. Close the browser tab and reopen Teams. If the icon remains, restart your browser completely. Then sign out and sign back in.
Messages Send on the Desktop App but Not on the Web
The desktop app uses a different network stack and authentication flow. If web delivery fails but desktop works, the issue is browser-specific. Clear the cache and disable any browser extensions that block cookies. Ad blockers and privacy extensions often interfere with Teams.
Delivery Fails Only for External Recipients
If you can chat with internal colleagues but not with people outside your organization, the external access policy is blocking the message. Ask your administrator to check the Teams admin center under Org-wide settings > External access. The option Users can communicate with other organizations must be enabled.
Teams on the Web Keeps Logging You Out
Frequent sign-out prompts indicate that third-party cookies are blocked. In Edge or Chrome, go to Settings > Cookies and site data. Allow cookies for the Teams domain and all subdomains. In Firefox, add the Teams domain to the exceptions list under Cookies and Site Data > Manage Exceptions.
Teams on the Web vs Teams Desktop App: Delivery Reliability
| Item | Teams on the Web | Teams Desktop App |
|---|---|---|
| Network dependency | Depends on browser network stack and WebSocket | Uses native network stack with more stable connection |
| Authentication refresh | Requires third-party cookies to refresh token | Uses system token store, fewer sign-out issues |
| Cache issues | Browser cache can corrupt and cause failures | Local app cache, less prone to corruption |
| Best for | Quick access on shared or restricted computers | Daily heavy use, large meetings, and file sharing |
Conclusion
You can now resend failed messages, clear the browser cache, and refresh your sign-in token to fix delivery failures in Teams on the web. Start with the resend option, then move to the hard refresh and cache clearing. If the problem persists, check your network and external access settings. For consistent reliability, install the Teams desktop app and use it for daily communication. As a final tip, press Ctrl+Shift+R after every major Teams update to avoid cache-related errors.