Teams app problems split between cache, sign-in, and the underlying Office install.

1. Restart Teams properly

Closing the window doesn't quit Teams — it runs in the background. To fully quit:

  • Right-click the Teams icon in the system tray → Quit
  • Then reopen from Start

If the system tray icon is missing, use Task Manager → end any Teams processes.

2. Sign out and back in

If Teams is stuck in a weird state:

  • Click your avatar (top right) → Sign out
  • Sign back in with your work account

This refreshes credentials and clears some session state.

3. Clear the Teams cache (Classic Teams)

For the older "Classic" Teams app:

  1. Fully quit Teams
  2. Windows + R → %appdata%\Microsoft\Teams
  3. Delete everything in that folder
  4. Reopen Teams

You'll have to sign in again. Your chats and channels are server-side, so nothing is lost.

4. Clear the new Teams cache

For the new Teams (which most users now have):

  1. Fully quit
  2. Windows + R → %LocalAppData%\Packages\MSTeams_8wekyb3d8bbwe\LocalCache
  3. Delete the contents
  4. Reopen

Alternatively, uninstall and reinstall the new Teams from Microsoft Store.

5. Reset Teams (Windows)

Settings → Apps → Installed apps → Microsoft Teams → three dots → Advanced options → Reset. This is a full clean reset.

6. Sign in issues — wrong account

If Teams keeps signing in to your personal Microsoft account when you want your work one:

  • Sign out
  • When the sign-in screen asks, type your work email — make sure it picks the work account, not consumer
  • If you have an "X" / cross to remove the wrong account from the sign-in dropdown, use it

7. "We couldn't connect" or red bar at top

Teams shows network connectivity issues with a red bar. Causes:

  • Network actually broken — fix the network
  • Proxy or firewall blocking Teams domains — IT issue
  • Your laptop time is wrong by more than a few minutes — fix the clock

8. Updates — Teams auto-updates

Teams updates in the background, but a stale install can break. Force an update:

  • Classic Teams: three dots → Check for updates
  • New Teams: updates via Microsoft Store

If updates aren't happening, your laptop may not have internet to the update servers. Verify network.

9. Teams is slow

Teams can be RAM-hungry. If your machine has 8 GB or less and several apps open:

  • Close browser tabs you're not using
  • Close Office apps you're not actively in
  • Quit Teams between meetings if you don't need notifications

The new Teams uses less memory than the old one — switch via the top-left toggle if you have both.

10. Meeting-specific issues

For audio/video/screen-share problems during a call, see [Teams meeting quality issues](/kb/troubleshooting-teams-meetings).

When to ticket

Open a ticket if:

  • Cache clears and reinstall don't fix it
  • Teams won't even open after a fresh install
  • Your account can sign in everywhere except Teams

Include the Teams version (Settings → About), the OS, and the exact error message.