Amazon error 90000: Feed could not be processed - file is malformedAmazon could not parse the file at all. Typical reasons: the two template header rows were deleted, the file was saved as .xlsx when a tab-delimited .txt was expected, the wrong feed type was chosen at upload, or the encoding mangled the header row.How to fix error 90000

Always start from a freshly downloaded template and paste your data into it - never rebuild the header rows by hand.

Keep both header rows intact: the template version row and the machine-readable field-name row.

Save as 'Text (Tab delimited) (*.txt)' if you are uploading the .txt variant, and pick the matching feed type in the upload dropdown.

Use UTF-8 encoding; Windows-1252 files with accented characters often fail here.

Test with 2-3 rows before uploading thousands.

All Amazon flat-file error codes