Managing personal Outlook.com account settings, security, and privacy
Hello Jim Wibskov,
Since these are fake Outlook accounts created in your names rather than your own accounts being compromised, I would report the fraudulent accounts directly to Microsoft through the Microsoft Security abuse reporting portal.
Because the accounts have reportedly been used for fraudulent Australian tax refunds, I would also report the identity misuse to the Australian Taxation Office and through the Australian Government’s ReportCyber service.
The FTC, IRS and IRS Form 14039 mentioned in the AI answer are US-specific and would not be the appropriate routes for an Australian tax-refund case.
Keep copies of any fraudulent account addresses, tax correspondence and other evidence for the reports.