Office 365 login: step-by-step sign-in guide

Updated on 24 Sep 2026 E-mail

Logging in to Office 365 is the process that gives you access to all Microsoft 365 services, such as Outlook, Teams, Word, Excel and OneDrive. Whether you work in the browser, a desktop application or a mobile app, the sign-in process always starts with your Microsoft account. In this detailed guide we explain step by step how to log in to Office 365 correctly, which common problems you may run into and how to solve them.

Microsoft 365 (formerly Office 365) is the most widely used office suite in the world. Millions of people in the Netherlands use it every day for email, documents and video meetings. A smooth login is essential to work productively. Below we cover every way to sign in, from the web version to the mobile app.

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The fastest way to reach your Office 365 environment is through your web browser. You don't need to install any software and you can sign in from any computer.

Open your web browser (Chrome, Firefox, Edge or Safari) and go to www.office.com or portal.office.com.
Click the "Sign in button in the top right corner of the screen.
Enter the email address linked to your Microsoft 365 account. This can be a business address (e.g. name@yourcompany.nl) or a personal Microsoft account.
Click "Next.
Enter your password on the next screen.
If your organization has enabled two-step verification (2FA), you'll receive a verification code by text message, through the Authenticator app or via a phone call confirmation. Enter this code. Read more about setting up two-step verification in our guide to setting up two-step verification.
Choose whether you want to stay signed in ("Yes on a trusted device, "No on a shared computer).
You now land on the Microsoft 365 dashboard, where you see all available apps.

From the dashboard you can open Outlook, Word Online, Excel Online, PowerPoint Online, Teams and OneDrive right away without installing any extra software.

Logging in to Outlook (webmail)

Outlook is the email application within Microsoft 365. You can go straight to Outlook without going through the Office dashboard first.

Step-by-step: opening Outlook webmail

Go to outlook.office.com or outlook.office365.com in your browser.
Sign in with your email address and password.
Complete two-step verification if required.
Your Outlook inbox loads with all your emails, calendar and contacts.

Don't have a business email address yet? Then check out our guide on creating a professional email address for your business.

Logging in to Microsoft Teams

Teams is the collaboration and communication tool of Microsoft 365. You can use Teams in the browser, in the desktop app or in the mobile app.

Opening Teams in the browser

Go to teams.microsoft.com.
Sign in with the same Microsoft 365 credentials you also use for Outlook.
Choose whether you want to use Teams in the browser or download the desktop app.
The first time, you'll be asked to allow notifications. This is recommended for the best experience.

Installing and signing in to the Teams desktop app

Download the Teams app from teams.microsoft.com/download or from the Microsoft 365 dashboard.
Install the application and launch it.
Enter your email address and click "Sign in.
Enter your password and complete 2FA verification if required.
Teams opens with your chats, channels and meetings.

The desktop versions of Word, Excel, PowerPoint and Outlook offer more functionality than the web versions. After installation, you need to activate the software with your Microsoft 365 account.

Activating and signing in to desktop apps

Open an Office application (for example Word) on your computer.
If you're not signed in yet, a sign-in screen appears. Click "Sign in.
Enter your Microsoft 365 email address.
Enter your password on the next screen.
The application checks your license and automatically activates all Office apps on your computer.
You now see your name and profile picture in the top right corner of the application, which confirms that you're signed in.

Note: You can activate Office 365 on up to 5 devices at the same time. If you reach that limit, you first need to deactivate a device via myaccount.microsoft.com.

The mobile Office apps (Outlook, Teams, Word, Excel, OneDrive) are available for iOS and Android. The sign-in process is almost identical on both platforms.

Step-by-step: setting up the mobile app

Download the app you want (e.g. Outlook or Microsoft 365) from the App Store (iPhone) or the Google Play Store (Android).
Open the app and tap "Add account or "Get started.
Enter your email address.
Enter your password.
Complete two-step verification if it's enabled.
Give the app the requested permissions (notifications, contacts, calendar).
The app syncs your data and is ready to use.

Tip: install the Microsoft Authenticator app on your phone. It lets you sign in quickly and securely without having to type a password every time.

Logging in to the Microsoft 365 Admin Portal

Administrators of a Microsoft 365 organization have access to the Admin Portal for user management, licenses and security settings.

Accessing the Admin Portal

Go to admin.microsoft.com.
Sign in with your administrator account (this account has the Global Administrator role or another admin role).
After signing in you see the admin dashboard with overviews of users, licenses, service health and billing.

From the Admin Portal you can create new users, reset passwords, assign licenses and configure security policies.

Resetting your Office 365 password

Forgot your password? Microsoft offers several ways to regain access.

Resetting your password yourself (self-service)

Go to the sign-in screen on office.com and enter your email address.
Click "Forgot password? or "Can't access your account?.
Choose a verification method: email to an alternate address, a text message to your phone number or the Authenticator app.
Enter the verification code you received.
Set a new password that meets the requirements (at least 8 characters, a combination of uppercase letters, lowercase letters, numbers and special characters).
Confirm the new password and sign in.

Important: Self-service password reset must be enabled by your administrator. If it isn't, contact your IT department or Microsoft 365 administrator.

Can't log in? Below you'll find the most common problems and their solutions.

1. Error message "Your account has been locked"

This happens when you've entered a wrong password too many times. The account is temporarily blocked to prevent misuse.

Solution: Wait 15 to 30 minutes and try again. In the meantime, use the "Forgot password" option to reset your password.
Contact your administrator if the problem persists.

2. Error code AADSTS50126: invalid password

You entered an incorrect password, or your password has expired.

Solution: Check that Caps Lock is off. Try resetting your password through the self-service portal.
Check that you're using the right account (work vs. personal).

3. Error code AADSTS50034: account does not exist

The email address you entered is not recognized by the system.

Solution: Check that you're using the correct email address. Your account may have been deleted, or you may be using the wrong domain.
Contact your IT administrator to verify that your account is active.

4. Error code AADSTS700016: application not found

The application you're trying to sign in with is not configured in your organization.

Solution: Use the correct URL to sign in (office.com, outlook.office.com). Contact your administrator if the problem occurs with a specific app.

5. Two-step verification isn't working

You don't receive a verification code, or the Authenticator app shows an error message.

Solution: Check that your phone is connected to the internet. Sync the time on your phone (Settings > Date & Time > Set Automatically).
Use an alternative verification method (text message instead of the app, or the other way around).
As a last resort, contact your administrator to temporarily reset your 2FA.

6. License problem: "No license assigned"

You can sign in but don't have access to certain applications.

Solution: Ask your administrator to check in the Admin Portal whether a valid Microsoft 365 license has been assigned to your account.
Check whether the license includes the apps you need (some licenses don't include Teams or the desktop apps).

The sign-in page doesn't load correctly, shows a blank white page or gets stuck in a redirect loop.

Solution: Clear your browser cache and cookies. Try another browser window in incognito/private mode. Disable browser extensions that may conflict (ad blockers, VPN extensions).
Try a different browser if the problem persists.

8. "Your organization has not approved this device"

Your organization enforces a device policy (Conditional Access) and your device doesn't meet the requirements.

Solution: Register your device through the Company Portal app (Intune). Make sure your operating system is up to date. Contact your IT department for the specific requirements.

A secure login protects not only your own data, but also that of your entire organization. Follow these best practices to secure your account as well as possible.

Security measure	Why it matters	How to set it up
Two-step verification (2FA)	Prevents unauthorized access even if your password leaks	Via this guide
Strong password	Harder for hackers to crack	At least 12 characters, a mix of letters, numbers and symbols
Password manager	Prevents password reuse	Use tools such as Bitwarden, 1Password or LastPass
Change your password regularly	Limits the damage from an undetected data breach	Change it every 90 days via myaccount.microsoft.com
Check for suspicious activity	Detects unauthorized sign-in attempts	View your sign-in history via mysignins.microsoft.com

Always sign out on shared or public computers. Don't just close the browser window, but explicitly click "Sign out".
Never click links in suspicious emails that ask you to sign in again. Always go to office.com yourself.
Keep your operating system and browser up to date to prevent security vulnerabilities.
Don't use public Wi-Fi without a VPN connection when you sign in to Office 365.
Check the URL before you sign in. Phishing sites look like the real sign-in page but use a different web address.

Microsoft has different portals for different purposes. Below is an overview of the most important URLs:

Service	URL	Purpose
Microsoft 365 Dashboard	office.com	Central starting point for all Office apps
Outlook Webmail	outlook.office.com	Email, calendar and contacts
Microsoft Teams	teams.microsoft.com	Chat, meetings and collaboration
OneDrive	onedrive.com	Cloud storage and file sharing
Admin Portal	admin.microsoft.com	Management of users and licenses
Account management	myaccount.microsoft.com	Password, security and devices
Sign-in history	mysignins.microsoft.com	Overview of recent sign-in attempts
Password reset	passwordreset.microsoftonline.com	Self-service password reset

Frequently asked questions

What is the difference between Office 365 and Microsoft 365?

In 2020, Microsoft renamed Office 365 to Microsoft 365. The services and the sign-in process have stayed the same. So "Office 365 login" refers to the same thing as "Microsoft 365 login". You use the same sign-in page and the same credentials.

Can I log in to Office 365 with multiple accounts at the same time?

Yes. In the browser you can use multiple accounts through different browser profiles or by opening an InPrivate/incognito window. In the desktop apps you can switch between accounts via your profile icon in the top right corner. The mobile Outlook app supports multiple accounts in the same app.

Why do I keep having to log in to Office 365 again?

This can have several causes: your browser automatically clears cookies when it closes, your organization has set a short session duration, or a Conditional Access policy is active. Check your browser settings and contact your IT administrator if the problem persists.

How do I log in to Office 365 if my password has expired?

Go to the sign-in page and try to sign in. Microsoft automatically shows a message that your password has expired and offers the option to set a new password. If self-service password reset is not enabled, contact your administrator.

Can I use Office 365 without an internet connection?

The desktop applications (Word, Excel, PowerPoint) work offline if you've previously activated them with your account. You can edit files locally; they sync automatically as soon as you're back online. The web versions on office.com require an active internet connection.

How do I set up two-step verification for my Office 365 account?

Go to myaccount.microsoft.com, click "Security info and add a verification method (Authenticator app, phone number or alternate email address). We recommend the Microsoft Authenticator app for the best security. Read our detailed guide to setting up two-step verification for a step-by-step explanation.

What should I do if I get error code AADSTS90072?

Error code AADSTS90072 means you're trying to sign in to an organization tenant you don't have access to. Check that you're using the correct email address. If you work with multiple organizations, make sure you select the correct account. Clear your browser cookies and try again.

How do I check which Microsoft 365 license I have?

Sign in at myaccount.microsoft.com and go to "Subscriptions. There you can see which licenses are linked to your account and which apps are included. If you're an administrator, you can view all licenses via admin.microsoft.com > Billing > Licenses.

This usually points to a license problem. Your account may not have a license assigned, or the assigned license doesn't include all apps. Contact your administrator to check your license and adjust it if needed.

How do I create a professional email address for Office 365?

To use Office 365 with your own domain name (e.g. name@yourcompany.nl), you need a business email address. Read our guide on creating an email address to learn how to set up a professional business email address that you can link to Microsoft 365.

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