Using Classic Outlook on Windows for personal email, calendar, and contact management
Hi, I'm John! I will help you with this.
To understand the setup, may I ask what type of email account this is? Is it Outlook.com/Hotmail, Gmail, Yahoo, or a work/school account with a custom domain?
Also, how was the account added in Classic Outlook? Was it added as Microsoft Exchange, IMAP, POP, or manually using server settings?
Please also check if the new emails appear when you sign in through webmail. For example, Outlook.com, Gmail.com, Yahoo Mail, or your email provider’s website.
That will help confirm if the issue is only with Classic Outlook or with the mailbox itself.