Thanks for posting your question in the Microsoft Q&A forum.
The import fails because editing the CSV, often adds hidden formatting or encoding changes so even if you didn’t touch the id column, its format may have been altered. Things like BOM characters, encoding changes, extra spaces, or blank lines can break Azure Migrate’s parser.
The fix is to edit the file in a plain text editor, keep the id column exactly as exported, save as UTF-8 with no extra characters, and make sure there are no hidden spaces or empty rows. Once the CSV is clean, the import should work.
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