Switching e-mail providers isn't always an easy affair, especially if you want to hold onto your old e-mail messages. And if you want to switch from Gmail, Google's use of labels instead of folders can throw another wrench into importing your messages.
In the past, moving your Gmail to Outlook.com required some manual steps and you'd lose your Gmail labels in the end. Now, Outlook.com has an import tool that walks you through importing your Gmail messages, and it even converts your Gmail labels to folders.
To use Outlook.com's Gmail import tool, click on the gear icon in Outlook.com, then choose "More mail settings." Under "Managing your account," click on "Import e-mail accounts," then on Google. You can also go to the Gmail import tool directly here.
On the import tool start page, click on the Options link, then decide if you want to change how to import your e-mail. By default, it will import your messages into existing folders and create new folders for any custom labels you used in Gmail. When you're ready to go, click Start.
Be sure to authorize Outlook.com to access your Gmail account when prompted. Depending on how many messages need to be imported, the import could take quite a while to complete. When it does finish, you'll receive an e-mail informing you.