Hi @Ron Thomas
Thank you for posting your question in Microsoft Q&A.
As your description, I understand that you're experiencing an issue where your Outlook business account is not receiving emails.
To better address this issue, could you please provide the following information for the following questions:
What build of Classic Outlook are you currently using?
Can you check with the sender to confirm whether the email was successfully sent? Did sender receive any Non‑Delivery Report (NDR) or bounce‑back message?
Additionally, does this issue affect only your account, or are other accounts in your tenant experiencing the same behavior?
In the meantime, you could try to follow these steps to troubleshoot it:
Check the Junk Email folder
Outlook’s spam filter can sometimes redirect legitimate emails to the Junk folder.
Open Outlook and select Junk Email from the left sidebar.
If you find the missing email, right‑click it > Move > Inbox.
When prompted, select the option to always trust emails from that sender, then click OK.
Check if Outlook is in Offline Mode
If Work Offline is enabled, Outlook will not send or receive new messages.
Open Outlook and go to the Send/Receive tab.
Look for the Work Offline button.
If it’s highlighted, click it to return Outlook to online mode.
Review Outlook Rules
A mail rule may be redirecting incoming email to another folder.
Click the File tab in Outlook.
Under Info, choose Manage Rules & Alerts.
In the Email Rules section, review your rules.
If you find one that affects incoming messages, uncheck it to disable it temporarily.
Please understand that our initial reply may not always immediately resolve the issue. However, with your help and more detailed information, we can work together to find a solution.
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