Trying to query microsoft defender for office 365 tenant that is written in Japanese characters but erroring out.

Hi Mark,

Welcome to Microsoft Q&A.

I understand how tricky it can be when working with international character sets in APIs.

To answer your question directly: Yes, the Microsoft Defender and Microsoft Graph APIs absolutely support non-ASCII (Unicode) characters, including Japanese.

The errors you're encountering are almost always related to how those characters are encoded in the API request itself, rather than a lack of support from the service.

1. If the Japanese characters are in the URL's query string (for example, in a $filter parameter), they must be properly URL-encoded (also called percent-encoding). Most modern scripting languages and tools (like Python's requests library or PowerShell's Invoke-RestMethod) do this automatically. However, if you are building the URL string manually, you need to ensure the non-ASCII characters are encoded first.
2. If the characters are in the JSON body of a POST request, make sure your Content-Type header correctly specifies the UTF-8 charset: Content-Type: application/json; charset=utf-8
3. If you're running a PowerShell or Python script, for instance, ensure the .ps1 or .py file is saved with UTF-8 encoding, not ASCII. Otherwise, the characters can be corrupted before they are even sent.

 Let me know if you need further assistance.

Best regards,

Alex | Microsoft Q&A Support Specialist

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