Your Microsoft 365 mailbox is ready. This guide covers everything you need on day one: signing in, reading your email in a browser, setting up Outlook on your computer and phone, installing Word and Excel, and what to do if you forget your password. Each section links to a detailed guide if you want more.
Before you start
- Your sign-in is your email address, for example
you@yourbusiness.co.uk, and the password your administrator gave you. (Administrators: your.onmicrosoft.comadmin login keeps working too.) - Have your phone to hand. Microsoft asks you to set up the free Microsoft Authenticator app the first time you sign in.
- If you also have a personal Microsoft account (Outlook.com, Hotmail, Xbox), use a private browser window for your first sign-in so the two don't get mixed up.
Your Microsoft 365 links
| What you want to do | Go to |
|---|---|
| Read and send email in a browser | outlook.office.com |
| Word, Excel, PowerPoint online and app downloads | office.com |
| Your files (OneDrive) | office.com, then select OneDrive (or use the OneDrive app on your computer or phone) |
| Teams chat and meetings | teams.microsoft.com |
| Change your password or security details | mysignins.microsoft.com |
| Manage users, licences and your domain (admins only) | admin.microsoft.com |
Step-by-step: get set up
- Sign in for the first time. Go to outlook.office.com, enter your email address and password, and choose a new password if asked. When you see More information required, select Next, install Microsoft Authenticator from the App Store or Google Play, choose Add account → Work or school account and scan the QR code on your screen. See Set up multi-factor authentication.
- Check your email works. You're now in Outlook on the web. Send yourself a test message from another address (for example your personal email) and reply to it. See Outlook on the web: complete guide.
- Install the Office apps on your computer (Business Standard and Premium). Go to office.com, select Install apps → Microsoft 365 apps, run the download and sign in with your work email when Word first opens. You can install on up to 5 PCs or Macs, 5 tablets and 5 phones. Business Basic includes the web and mobile apps only. See Install Microsoft 365 apps.
- Add your email to Outlook on your computer. Open Outlook, enter your work email address and sign in. Outlook finds the settings automatically: there are no server names to type. See Outlook for Windows or Outlook for Mac.
- Add your email to your phone. Install the free Microsoft Outlook app from the App Store or Google Play and sign in with your work email. We recommend the Outlook app over the phone's built-in Mail app. See Set up Microsoft 365 email on iPhone and Android.
- Add your signature. In Outlook on the web go to Settings (gear icon) → Mail → Compose and reply. Signatures in Outlook on the web and Outlook for Windows and Mac sync between them. See Add an email signature.
Everyday tasks
- Out of office: Set up automatic replies.
- Forward email to another address: Forward Microsoft 365 email.
- Sort email automatically: Create inbox rules.
- Share your calendar: Share calendars inside and outside your organisation.
- Store and share files: OneDrive and SharePoint basics.
- Chat and video meetings: Microsoft Teams: getting started.
- Scan-to-email from an office printer: Printer SMTP settings.
Troubleshooting
I've forgotten my password
Ask your Microsoft 365 administrator to reset it (admin guide). If your organisation has turned on self-service reset, you can use passwordreset.microsoftonline.com instead.
I've got a new phone and can't approve sign-ins
Your administrator can reset your sign-in methods so you can set up Authenticator again. If you're the only administrator, open a ticket and we'll help.
Outlook keeps asking for my password
See Outlook keeps asking for a password? How to fix and repair Outlook.
Word or Excel says "Unlicensed Product"
Sign out of the app (File → Account → Sign out) and sign in again with your work email. If it still says unlicensed, ask your administrator to check that your plan includes the desktop apps.
Last reviewed: October 2026
