Overview

Error 90011 is a feed submission error that Amazon sellers encounter when uploading inventory files or product listings through Seller Central. This error occurs when your file contains duplicate column headers or invalid/empty column headings, preventing Amazon's system from processing your data. Understanding how to quickly resolve this error can save sellers significant time and avoid delays in getting products listed or updated.

Key Points / What Sellers Need to Know

• Duplicate columns trigger the error - If your upload file contains the same column header more than once, Amazon's system cannot determine which column to use and will reject the entire file with Error 90011.
• Empty or invalid headers also cause failures - Column headings in row two of your file must match the expected format from Amazon's template. Blank or malformed headers will prevent your feed from being processed.
• The fix is straightforward - In most cases, downloading a fresh template from Seller Central and re-entering your data will resolve the issue immediately.
• No data loss occurs - This error stops the file from being processed before any changes are made, so your existing listings remain unaffected while you correct the file.

What Causes Error 90011

This error typically happens when sellers manually edit their inventory feed files in spreadsheet software like Excel or Google Sheets. During the editing process, columns can accidentally be copied, headers can be inadvertently deleted, or formatting changes can corrupt the expected column structure. It can also occur when sellers attempt to merge data from multiple templates or when a file is saved in an incorrect format that alters the header row. Sellers who work with large catalog files across multiple editing sessions are particularly susceptible to this issue, as incremental changes can introduce subtle formatting problems that are easy to overlook.

How to Fix the Error

There are two approaches to resolving Error 90011. The quickest method is to download a fresh copy of the inventory file template directly from Seller Central. Navigate to the template download section, select the appropriate template for your product category, and then re-enter or paste your product data into the clean file. This ensures all column headers are correctly formatted and positioned. Alternatively, if you prefer to fix your existing file, carefully review row two to identify any duplicate column names. Remove the extra instance of any duplicated column, making sure you preserve the data in the correct column. Also check that no column headers are blank or contain unexpected characters. Once you have made corrections, save the file and resubmit your feed through Seller Central.