If you have multiple accounts in Outlook, when you compose a new email message, Outlook picks the default account as the From account.However, if you want to Reply, Reply All, or Forward a message, Outlook will send your message with the same account the original mail was sent to.For example, Cheryl has two accounts.

A Microsoft account gives you access to Microsoft products and services with just one login.

Microsoft 优先考虑帐户安全性，并且会在未经你许可的情况下阻止用户登录。 当我们发现有从新位置或新设备进行登录的尝试时，我们会向你发送电子邮件和短信通知来帮助保护帐户。

Find out how to back up your apps, files, photos, and preferences on your Windows PC with File History and other tools.

Find out more about Xbox digital codes and gift cards, and how to troubleshoot issues redeeming content.

When your old email address or phone number doesn't suit you anymore—but you want to retain your contacts, online storage, subscriptions, and settings—you can add a new email address or phone number as an alias to your existing Microsoft account.

Sign in to account.microsoft.com, then select Order History on your Rewards page.

See an alert in a pop-up window on the bottom of Windows desktop when new email messages arrive in your Outlook Inbox.

Learn how to change app notifications, banners, and sound settings in Windows.

Learn how to block someone or add email addresses to the safe senders list in Outlook on the web.