First of all, you to determine the isolation of the mail there is no problem, your company's mail can be directly through the IE login? If you can, first log in directly through IE, and then manually delete the spam mail in your mailbox. Then you can try to receive emails through OUTLOOK.
Additionally, you can quarantine spam through the mail rules under OUTLOOK. Set it up to whitelist your old boss's mail address and let any mail he sends out go through.
Give a Microsoft official address for similar information
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