Troubleshooting Microsoft 365

Something not working as expected in Microsoft 365? This guide covers the most common issues and how to fix them — in plain English, step by step.

First: check if Microsoft is having a problem

Before troubleshooting your own setup, check whether Microsoft's services are experiencing an issue:

• In the admin center: Go to admin.microsoft.com and check the Service health section in the left menu.
• Publicly: Visit status.office.com to see current service status.

If there's a known outage affecting your service, the fix is to wait. Microsoft will resolve it and post updates.

Sign-in problems

"I can't sign in — it says my account doesn't exist"

• Double-check the email address. It should be your work email (for example, you@yourcompany.com), not a personal Gmail or Hotmail address.
• Ask your admin to confirm your account is active in Users → Active users.

"I forgot my password"

• On the sign-in page, click Forgot my password and follow the reset steps.
• If self-service reset isn't set up, ask your admin to reset your password.

"I can't get through the multi-factor authentication step"

• If you can't access your authenticator app, look for alternative methods on the sign-in screen (text message, backup code, etc.).
• If you're completely locked out, your admin can reset your MFA settings from the admin center. See Turning on multi-factor authentication for admin steps.

"I keep getting signed out"

• Your organization may have set short session timeouts. Try signing in again and checking "Don't show this again" if prompted.
• Clear your browser's cookies and try again.
• Make sure your browser allows cookies from microsoft.com and office.com.

Email problems (Outlook)

"My emails aren't sending"

• Check your internet connection.
• Check if your mailbox is full — if you're over quota, Outlook may block sending. See Storage & quotas.
• Check the Outbox folder — sometimes emails get stuck there. Try opening and resending.
• If using the desktop app, try sending from the web version at outlook.office.com to see if the issue is with the app.

"I'm not receiving emails"

• Check your Junk Email folder — emails may be going there incorrectly.
• Check your inbox rules — a rule may be moving emails to a folder you haven't noticed.
• Ask the sender to resend and check if they receive a bounce-back message.
• If your domain was recently added to Microsoft 365, check that DNS / MX records are fully updated. See Adding a domain.

"Outlook is slow or crashing"

• In the web version, try clearing your browser cache and refreshing.
• In the desktop app, try running Outlook in safe mode: hold Ctrl while opening Outlook (Windows) to bypass any problematic add-ins.
• Check for pending Windows updates — outdated systems can cause app instability.

OneDrive sync problems

"Files aren't syncing"

• Click the OneDrive icon in your system tray (Windows) or menu bar (Mac) to see the sync status. It may show a specific error message.
• Make sure you're signed in to OneDrive with the correct work account.
• Pause and resume syncing from the OneDrive icon menu.
• Restart the OneDrive app: right-click the icon and choose Quit OneDrive, then reopen it.

"There's a sync conflict"

When two people edit the same file simultaneously and the versions conflict, OneDrive creates a conflicting copy. You'll see a file with "conflict" or a person's name in the filename. Open both versions, compare the differences, keep the one you want, and delete the other.

Teams problems

"I can't join a meeting"

• Check that your browser allows camera and microphone access for Teams.
• Try joining from a different browser (Microsoft Edge or Chrome work best with Teams on the web).
• Ensure your internet connection is stable — Teams calls need a reasonable upload and download speed.

"My audio or video isn't working in a meeting"

• Check your device settings in the meeting pre-join screen — make sure the right microphone and camera are selected.
• Check that no other application is using your microphone or camera at the same time.

App errors

"I get an error saying my license has expired or isn't valid"

• This usually means a license hasn't been assigned to your account, or the subscription has lapsed.
• An admin should check your license status in Users → Active users, then check Billing → Your products to see if the subscription is active.

Common questions

Related guides

• Signing in to Microsoft 365
• Resetting a user's password
• Turning on multi-factor authentication
• Storage & quotas in Microsoft 365
• Adding a domain to Microsoft 365

Learn more

• Microsoft 365 service status
• Microsoft 365 support — admin center
• Microsoft 365 troubleshooting — Microsoft Learn