---
title: Outlook and Microsoft 365 Sign-in Issues
category: Accounts
summary: A user can't sign in to Outlook, Teams, Word/Excel or the Microsoft 365 web portal, or is stuck in a sign-in loop.
applies_to: Outlook desktop, Outlook on the web, Microsoft 365 apps on Windows
related: 05-password-reset-account-lockout, 06-phone-wont-sync-email, 03-wifi-not-connecting
---

## Symptoms

- Outlook keeps asking for the password, or shows "Disconnected" / "Need password".
- Office apps say "Sign in to activate" or "Unlicensed Product".
- The sign-in page loops, or says the account doesn't exist or is blocked.
- MFA codes or approval requests never arrive.
- Error messages such as "Need admin approval" or "Something went wrong".

## Before you start

- **Can the user sign in on the web?** Open a private/incognito browser window and go to the Microsoft 365 portal (`office.com`). Web works but the desktop app doesn't = a local app/credential problem. Web fails too = an account, license, network or service problem.
- Does this affect one user or many? Many users at once suggests a service issue. Check Service health in the Microsoft 365 admin center (admins only), or tell your lead.
- Has the password, phone, or MFA method changed recently?

## Steps

1. **Check the account first:** is it locked, expired, or blocked from sign-in? (See *Password Reset and Account Lockout*.) In the admin center confirm the user has a **license** assigned.
2. **Check date, time and network.** Wrong clock time can break sign-in. Make sure the PC has internet (see *Wi-Fi Not Connecting*) and isn't on a captive-portal network.
3. **Sign out of Office:** in any Office app go to File > Office Account > **Sign out**, close all Office apps, then sign in again.
4. **Clear stored credentials** (Windows): Control Panel > Credential Manager > **Windows Credentials**. Remove entries related to Office / Outlook / Microsoft (for example names beginning with `MicrosoftOffice16`, or containing `outlook.office365.com`). Restart Outlook and sign in again. Only remove Microsoft-related entries.
5. **Check "Access work or school":** Settings > Accounts > Access work or school. Make sure the work account is listed and not showing an error. If the device has a stale entry, disconnecting and reconnecting may be required, but do this only if you know it's allowed for managed devices.
6. **MFA problems:**
    - Check the phone has a connection and the authenticator app's notifications are allowed.
    - If the user has a new phone or the method is lost, an admin verifies identity then resets or re-registers the authentication method.
7. **Start Outlook in Safe Mode** to rule out add-ins: press `Win + R`, type `outlook.exe /safe`, Enter. If it works, disable add-ins (File > Options > Add-ins).
8. **Create a new Outlook profile:** Control Panel > Mail (Microsoft Outlook) > **Show Profiles** > Add. Choose the new profile as the default, open Outlook, and let it re-download the mailbox. (Cached local items will re-sync from the server; check nothing is stored only locally, like old `.pst` files, before removing the old profile.)
9. **Update and repair Office:** File > Office Account > Update Options > Update Now. If still failing: Settings > Apps > Installed apps > Microsoft 365 > Modify > **Quick Repair** (then **Online Repair** if needed).
10. **Microsoft Support and Recovery Assistant (SaRA)** is a free Microsoft diagnostic tool that can detect many Outlook/Microsoft 365 sign-in problems. Check that your organisation allows it before using it.
11. **Read the exact error** and write it down. Searching Microsoft's documentation for the exact error code usually gives the next step.

## Escalate when

- "Need admin approval", conditional-access or "blocked by your organisation" messages (needs an admin).
- The user has no license, or the license assignment is wrong.
- Many users are affected (possible Microsoft service incident).
- You think the account was compromised (unexpected MFA prompts, mail rules the user didn't make, sent mail they didn't write). That is a **security incident**.
- A mailbox appears missing or corrupted.

## Ticket note template

```
Issue: Cannot sign in to <Outlook desktop / Outlook web / Teams / Office apps>
Exact error message / code: 
Scope: one user / several | Started: | Recent changes (password, phone, device):
Web sign-in (private window): works / fails | License assigned: Y/N/unknown
Actions: signed out of Office | cleared Credential Manager entries | Safe Mode test | new profile | Quick/Online Repair
MFA status: working / needs reset (identity verified by <method>)
Result: Fixed / Not fixed
Next step / escalated to: 
```