“Unable to Authenticate” – Login Authentication Fails in SharePoint
The “Unable to Authenticate” error occurs in SharePoint when a user is unable to log in due to issues such as incorrect credentials, account lockout, expired passwords, security policies, or authentication configuration issues. This guide provides a detailed step-by-step process to troubleshoot and resolve this issue comprehensively.
Step 1: Verify Your Username and Password
One of the most common reasons for authentication failure is incorrect login credentials.
How to check your credentials:
- Ensure that you are using the correct email address associated with your SharePoint account.
- Re-enter your password carefully (ensure that Caps Lock is off).
- If your browser auto-fills your password, try entering it manually.
- Attempt to log in on a different device or browser.
If you forgot your password:
- Click Forgot password? on the login page.
- Follow the password reset instructions sent to your email.
- Create a new password and log in again.
Step 2: Check for Account Lockout
Many organizations have security policies that temporarily lock accounts after multiple failed login attempts.
How to check if your account is locked:
- Try logging in from another device or browser.
- Attempt to access another Microsoft 365 service (e.g., Outlook, Teams).
- If you receive a message like “Your account is locked”, you must wait for the lockout period to end or request manual unlocking.
How to unlock your account (if locked):
- Go to Microsoft’s account recovery page.
- Follow the unlock instructions sent to your email or phone.
- If this does not work, contact your IT administrator to manually unlock your account.
Step 3: Verify Multi-Factor Authentication (MFA) Requirements
Many organizations require Multi-Factor Authentication (MFA), which means you must enter a secondary verification code to log in.
How to check if MFA is required:
- After entering your username and password, check if you are asked for a verification code.
- If you don’t receive a code, check:
- Your email (if email-based authentication is enabled).
- Your phone (for SMS authentication).
- Microsoft Authenticator App (if used for MFA).
What to do if you cannot complete MFA:
- Click Resend Code and try again.
- If you no longer have access to your authentication method, contact your IT support team to reset MFA.
Step 4: Clear Browser Cache and Cookies
Sometimes, stored cookies and cache cause login failures.
How to clear cache and cookies:
- Open Google Chrome (or your browser).
- Press Ctrl + Shift + Delete (Windows) or Cmd + Shift + Delete (Mac).
- Select Cookies and Cached Data.
- Click Clear Data and restart the browser.
Then, try logging in again.
Step 5: Try a Different Browser or Incognito Mode
If you are experiencing authentication issues in one browser, try another.
How to test using Incognito Mode:
- Open a private/incognito window:
- Chrome: Ctrl + Shift + N
- Edge: Ctrl + Shift + N
- Firefox: Ctrl + Shift + P
- Visit SharePoint’s login page and try logging in.
If it works in Incognito, then your browser might have corrupt cookies or cached credentials.
Step 6: Check Organizational Security Policies
Your organization may enforce security policies that restrict logins.
How to check if login is restricted:
- Try logging in from a different Wi-Fi network (e.g., use a mobile hotspot).
- Check if your company requires a VPN for external access.
- If you are logging in from a new device or location, Microsoft may block access temporarily.
Solution:
- If blocked, contact your IT department to request access.
Step 7: Verify if Your Account is Disabled or Expired
If your account has been disabled or expired, authentication will fail.
How to check account status (For IT Admins):
- Open Microsoft 365 Admin Center.
- Go to Users → Active Users.
- Search for the user’s account and check:
- Account status (active or disabled).
- Password expiration date.
Solution:
- If the account is disabled, an admin must re-enable it.
- If the password is expired, reset it via Microsoft 365 Admin Center.
Step 8: Reset Your Password (For Users)
If your password is expired or compromised, reset it.
How to reset password in Microsoft 365:
- Go to Microsoft’s password reset page.
- Enter your email and follow the verification steps.
- Set a new password and log in again.
For company-managed accounts:
- Contact IT support for a manual password reset.
Step 9: Check for Conditional Access Policies (For IT Admins)
Your organization may have Conditional Access Policies that restrict authentication.
How to check Conditional Access Policies (Admins only):
- Open Azure Active Directory (Azure AD).
- Navigate to Security → Conditional Access.
- Check if:
- Your account is blocked due to device, location, or app restrictions.
- Policies require a compliant device (e.g., company-managed laptop).
Solution:
- Ask IT to grant you an exception or configure your device to meet security requirements.
Step 10: Check Authentication Protocols (For IT Admins)
Some authentication protocols (e.g., legacy authentication) may be disabled by IT.
How to check authentication settings (Admins only):
- Open Azure AD Admin Center.
- Navigate to Security → Authentication Methods.
- Verify if:
- Modern authentication is required.
- Legacy authentication (Basic Auth) is disabled.
Solution:
- Ensure that the correct authentication method is enabled for your account.
Step 11: Verify SharePoint Login URL (For Users)
Ensure you are logging into the correct SharePoint portal.
Correct SharePoint Login URLs:
- For Microsoft 365 users:
- For on-premises SharePoint:
- Contact your IT team for the correct URL.
Step 12: Contact IT Support or Administrator
If none of the above steps resolve the issue, contact IT support and provide:
- Your email address.
- The exact error message received.
- The steps you have already tried.
- A screenshot (if possible).
An administrator can check logs, security settings, and account status to resolve authentication failures.