Hi G, Janapriya (external - Service),
Welcome to Microsoft Q&A Forum! Have a good day and I hope you're doing well!
Could you please confirm if you are using a Microsoft 365 Business account (provided by your organization) or a Personal account (such as Outlook.com, Hotmail.com)?
Since you selected the "For business" category, I will guide you through troubleshooting steps tailored for a business organization environment. Assuming you are using a Business account, please try the following troubleshooting steps in order:
I. Check Outlook on the Web (OWA): First, please log in to outlook.office.com via a web browser. Check if the missing emails are visible there. If they are on the Web but not on your Desktop app, it indicates a synchronization issue with your Classic Outlook client.
II. Check Junk Email and "Focused" Inbox
1. Junk Folder: Check your Junk Email folder to see if the emails were wrongly filtered there.
2. Focused Inbox: If you have the "Focused Inbox" feature enabled, please click on the Other tab to ensure the emails didn't land there.
3. Use the Search bar at the top, type the exact email address of the sender, and press Enter to double-check if the emails are hidden in a different folder.
III. Check Blocked Senders List: It is possible the sender was accidentally added to the Blocked list.
1. In Classic Outlook, go to the Home tab, click Junk > select Junk E-mail Options.
2. Go to the Blocked Senders tab.
3. Check if the sender's email address is listed there. If yes, select it and click Remove.
Reference: Overview of the Junk Email Filter
IV. Check Inbox Rules: You might have a rule that automatically moves or deletes emails from these specific people.
1. Go to File > Manage Rules & Alerts.
2. Review the list for any rules involving the sender's name or email address. If you find any suspicious rules, try disabling them.
V. If you have performed all the steps above and still cannot find the emails (even on the Web), and since you are an end-user, please reach out to your organization's IT Department/Admin immediately.
1. Check Quarantine: Ask your Admin to check if the emails from these senders are stuck in the Microsoft Defender Quarantine (due to security policies). If they are, the Admin can release them for you.
Reference: Quarantined email messages in cloud organizations
2. Run a Message Trace: Ask your Admin to run a Message Trace for the missing emails. This will show exactly if the email reached the server, if it was delivered to your inbox, or why it failed.
Reference: Message trace in the new Exchange admin center in Exchange Online
I hope this helps you narrow down the issue. Please give these steps a try and let me know how it goes. If you have any updates, or if I misunderstood anything, feel free to reply so I can provide more accurate troubleshooting steps.
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