Use the supported sign-in path for Outlook.com accounts in the Gmail app and, if that fails, fall back to manual setup.
- In the Gmail app, update to the latest version via Google Play if not already.
- Open Gmail and go to Settings → Add account.
- Select Outlook, Hotmail, and Live.
- Enter the full Outlook.com email address and tap Next.
- When redirected to Microsoft sign-in, complete the sign-in flow (including any recovery email or verification steps) and accept the permissions prompt.
- When prompted how often to sync, choose a sync interval, confirm the account name and display name, then finish.
If the built-in Outlook/Hotmail option continues to fail with “unable to authenticate”, configure the account using the Exchange/Microsoft 365 path instead:
- In Gmail, go to Settings → Add account → Exchange and Microsoft 365.
- Enter the Outlook.com email address and tap Next.
- Enter the password and tap Next.
- On the incoming server settings screen, if shown, set the server to outlook.office365.com.
- Follow the prompts for security/device permissions and sync settings.
- If an email appears saying Action Required to Sync Email, open it and tap Use another Mail app instead to complete setup.
If still unable to authenticate using Exchange, set the account up as IMAP in Gmail (email only, no calendar/contacts):
- In Gmail, go to Settings → Add account → Other.
- Enter the Outlook.com address and tap Manual Setup.
- Choose Personal (IMAP).
- Enter the password and tap Next.
- For incoming and outgoing server settings, use the Outlook.com IMAP/SMTP values provided by the email provider (for SMTP, use smtp-mail.outlook.com, security type TLS, port 587).
- Complete the prompts and finish setup.
If none of these paths work, use the Microsoft Outlook for Android app, which is the primary supported client for Outlook.com on Android.
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