Outlook and Mail for Windows 10 require access to your Gmail folders. Check to see if the folders are visible in IMAP.

• Start Outlook.
• Select File from the File menu.
• Select Add Account from the drop-down menu.
• Select New in the pop-up window that appears.
• Click Connect after entering your Gmail address.
• Then click Connect after entering your password.
• Gmail will be added to Outlook.
• After that, click Done. That's it, Gmail is now available!
• Go to Gmail.com in your browser.
• Select Settings > Settings from the menu bar.
• Select the Labels tab from the drop-down menu.
• Make that Inbox, Sent Mail, Trash, and All Mail are all set to show in IMAP.
• Other labels that you want to view in Outlook or Mail for Windows 10 can be shown in IMAP by selecting Show in IMAP.

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