How to Troubleshoot Teams Login and Sync Issues

Applies to: Microsoft Teams (Desktop, Web, Mobile)
Article Type: Troubleshooting
Last Updated: 2026-05-19

Summary

This article walks you through fixing common Microsoft Teams login problems — including sign-in loops, stuck loading screens, "We're sorry — we've run into an issue" errors, and sync failures where messages or channels do not update. Most of these steps can be performed without administrator rights.

Prerequisites

• A Microsoft 365 account with a Teams license.
• An active internet connection (verify by opening a web page in your browser).
• Windows 10 or Windows 11 (or macOS for Mac users).

Instructions

1. Check If Teams Is Down (Service Outage)

Before troubleshooting your device, verify that the issue is not a Microsoft service outage.

1. Open your browser and go to the Microsoft 365 Service Health page: https://status.office.com.
2. Look for any reported issues with Microsoft Teams.
3. Alternatively, check https://downdetector.com/status/teams/ for user-reported outage trends.
4. If there is a known outage, no local troubleshooting will help — wait for Microsoft to resolve it.

2. Try the Teams Web App

Testing the web version helps isolate whether the issue is with the desktop app or your account.

1. Open your browser and go to https://teams.microsoft.com.
2. Sign in with your work credentials.
3. If the web version works normally, the issue is specific to your desktop app — proceed to Step 3.
4. If the web version also fails, the issue may be account-related — proceed to Step 6.

3. Restart Microsoft Teams (Fully)

Closing the Teams window does not always quit the app — it may still be running in the background.

1. Right-click the Teams icon in the system tray (bottom-right corner, near the clock).
2. Select Quit (or Close).
3. Wait 10 seconds.
4. Reopen Teams from the Start menu or taskbar.
5. If Teams is not in the system tray, open Task Manager (press Ctrl + Shift + Esc), find Microsoft Teams in the list, click it, and click End task. Then reopen Teams.

4. Clear the Teams Cache

Corrupted cache files are the most common cause of Teams login loops and sync issues. Clearing the cache forces Teams to download fresh data.

1. Fully quit Teams (see Step 3 — make sure the process is not running in Task Manager).
2. Press Win + R to open the Run dialog.
3. Type the following path and press Enter:
   • New Teams (Teams 2.x): %localappdata%\Packages\MSTeams_8wekyb3d8bbwe\LocalCache\Microsoft\MSTeams
   • Classic Teams: %appdata%\Microsoft\Teams
4. Select all files and folders inside this directory and delete them.
5. Reopen Teams. You will need to sign in again, and Teams will rebuild its cache from scratch.

See How to Clear the Microsoft Teams Cache for detailed step-by-step instructions for each Teams version.

5. Clear Browser Credentials and Cached Logins

If Teams is stuck in a sign-in loop, stale authentication tokens may be causing the problem.

Clear Credentials in Windows

1. Click Start and type Credential Manager.
2. Open Credential Manager and click the Windows Credentials tab.
3. Look for entries that mention Microsoft Teams, MicrosoftAccount, or office.com.
4. Click each one and select Remove.
5. Restart Teams and sign in fresh.

Clear Browser Cookies (for Teams Web)

1. If the issue is in the browser, clear cookies for teams.microsoft.com and login.microsoftonline.com.
2. See How to Clear Browser Cache and Cookies for browser-specific instructions.

6. Verify Your Account and License

Sometimes the issue is not with Teams but with your Microsoft 365 account.

1. Open your browser and go to https://portal.office.com.
2. Sign in with your work credentials.
3. If you cannot sign in, your account may be locked or your password may have expired. See How to Change Your Microsoft 365 Password, or ask IT to unlock the account and tell you whether the password has expired.
4. If you can sign in, click the App launcher (waffle icon) and check if Teams is listed. If it is missing, your account may not have a Teams license — ask IT to assign you a Teams license, and mention that Teams is absent from your app launcher at https://portal.office.com.

7. Check Your Network Connection

Teams requires a stable internet connection. Certain networks (VPNs, guest Wi-Fi, restrictive firewalls) can block Teams traffic.

1. Open your browser and navigate to any website to confirm basic internet access.
2. If you are on a VPN, try disconnecting and reconnecting to see if Teams works without it.
3. If you are on a guest or public Wi-Fi network, some networks block Teams traffic. Switch to a trusted network or use a mobile hotspot.
4. If you are on your office network and Teams is not connecting, ask IT to confirm that the firewall and proxy allow Microsoft Teams traffic, and tell them Teams works on a mobile hotspot but not on the office network.

8. Update or Reinstall Teams

An outdated Teams app can cause login and sync issues.

Update Teams

1. Open Teams and click the three-dot menu (⋯) next to your profile picture.
2. Select Check for updates (Classic Teams) or About Teams (New Teams).
3. If an update is available, Teams will download and install it. Restart Teams when prompted.

Reinstall Teams (If Updates Don't Help)

1. Open Settings (press Win + I).
2. Navigate to Apps > Installed apps.
3. Find Microsoft Teams, click the three-dot menu (⋯), and select Uninstall.
4. Restart your computer.
5. Download the latest version from https://teams.microsoft.com/download and install it.
6. Sign in with your work credentials.

9. When to Contact IT

Three details turn a Teams ticket into a one-reply fix: the exact error wording (a screenshot is ideal), whether the same account works at https://teams.microsoft.com in a browser, and which of the steps above you already tried.

Contact the IT helpdesk if:

• You have followed all steps above and Teams still does not work.
• Your account is locked or you cannot sign in to any Microsoft 365 service.
• You receive an error mentioning Conditional Access or device compliance — these are IT-managed security policies.
• Teams works on other devices but not on your primary computer.
• You suspect your Teams license has been removed.

Troubleshooting

DANGER

Clearing the Teams cache (Step 4) resolves the vast majority of desktop login and sync issues. If you are stuck in a sign-in loop or Teams is showing stale data, this should be your first action after a basic restart.

Symptom / Error	Potential Cause	Solution
Stuck on "Loading Microsoft Teams…"	Corrupted cache or stale login tokens	Clear the Teams cache (Step 4), then restart Teams.
Sign-in loop (asks for password repeatedly)	Cached credentials are invalid or expired	Clear credentials in Credential Manager (Step 5) and clear the Teams cache (Step 4).
"We're sorry — we've run into an issue"	Account issue or corrupted app data	Try the web version (Step 2). If it works, clear cache and reinstall (Steps 4 and 8).
Chats and channels do not update	Sync failure due to cache corruption	Clear the Teams cache (Step 4). Check the network connection (Step 7).
"You're offline" but internet works	Teams network check is failing	Disconnect and reconnect Wi-Fi or VPN. If it only fails on the office network, ask IT to confirm the firewall allows Teams traffic, naming the network or VPN profile you were on.
Presence status is wrong	Teams sync is delayed or stuck	Restart Teams fully (Step 3). Set your status manually as a temporary workaround.
Teams app opens but shows a blank white screen	GPU rendering or app corruption issue	Clear the cache (Step 4). If it persists, reinstall Teams (Step 8).
"Your organization has disabled this feature"	Conditional Access or compliance policy	Quote the message word for word in a ticket, name the feature you were using, and ask whether it can be enabled for your account.

Related Articles

• How to Clear the Microsoft Teams Cache
• How to Fix Audio or Video Not Working in Microsoft Teams
• How to Clear Browser Cache and Cookies
• How to Change Your Microsoft 365 Password
• How to Troubleshoot Slow Internet or Network Performance (User-Level Steps)
• How to Troubleshoot VPN Connection Issues (User-Level Steps)
• How to Fix Common Computer Glitches by Restarting

Did this solve your problem?