Overview

Error 99036 is a common validation error that Amazon sellers encounter when uploading product listing templates or feed files through Seller Central. This error indicates that one or more attribute values in your submission don't meet Amazon's formatting requirements, character limits, or accepted value lists. Understanding how to diagnose and fix this error can save sellers significant time during the listing creation and update process.

Key Points / What Sellers Need to Know

• Invalid attribute values trigger this error — Error 99036 fires when a column in your upload template contains a value that doesn't conform to Amazon's requirements for that specific field.
• Format mismatches are a leading cause — If the data you've entered doesn't follow the expected format for a given attribute (such as entering text where a number is required), the system will reject the submission.
• Character limits matter — Each product attribute has a maximum allowed character count, and exceeding it will result in this error on the affected field.
• Special characters are often restricted — Certain symbols like "?" and "@" are not permitted in specific fields such as SKU, and including them will cause the upload to fail.
• Drop-down values must be selected, not typed — For fields that have a predefined set of accepted values, manually copying and pasting a value instead of selecting it from the drop-down list can introduce invisible formatting differences that trigger the error.

Common Causes

The root cause of Error 99036 almost always comes down to a mismatch between what you've entered and what Amazon expects for a particular product attribute. This can happen in several ways. The most straightforward is entering a value in the wrong format — for instance, providing a date in an unexpected format or including alphabetic characters in a numeric-only field. Another frequent trigger is exceeding the maximum character length for a given attribute, which varies from field to field. Sellers who work with large catalogs and use bulk upload templates are especially prone to this when copying data from external spreadsheets or databases without first checking Amazon's character constraints.