Hello @Teddy Setiawan
Thank you for reaching out to Microsoft Q&A.
Error Message: Unknown CSV header found
Based off your error message and referencing the Bulk create users in Microsoft Entra ID documentation, can you make sure that you didn't add any additional headers?
For more info - Additional guidance
- The first two rows of the upload template must not be removed or modified, or the upload can't be processed.
- The required columns are listed first.
- We don't recommend adding new columns to the template. Any additional columns you add are ignored and not processed.
- We recommend that you download the latest version of the CSV template as often as possible.
- Make sure to check there is no unintended whitespace before/after any field. For User principal name, having such whitespace would cause import failure.
- Ensure that values in Initial password comply with the currently active password policy.
I'll share the steps I took below to hopefully help point you in the right direction and resolve your issue.
- Within MS Entra ID -> Users
- Select Bulk Operations ->Bulk Create
- Download the csv template.
- Filled in user information starting at line 4 within the CSV file.
Note: If you are adding only one entry using the CSV template, you must preserve row 3 and add your new entry to row 4.
- Uploaded the CSV file to bulk create the users.
For more info - Bulk create users in Microsoft Entra ID
I hope this clarifies things. Please contact us if you have any additional questions.
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