---
title: I get 400 Bad Request errors when uploading objects
description: Solve 400 Bad Request errors when uploading objects with AES256 encryption headers
tags: sse amazon-s3 aes 256 error put header server side encryption fail reject
dates:
  validation: 2025-11-07
  posted: 2025-11-07
---
import Requirements from '@macros/iam/requirements.mdx'


<Requirements />

- [Owner](/iam/concepts/#owner) status or [IAM permissions](/iam/concepts/#permission) allowing you to perform actions in the intended Organization

## Problem

When uploading an object, I get an error similar to the following:

```bash
HTTP 400 Bad Request: InvalidArgument.
```

## Cause

Scaleway Object Storage previously accepted requests containing the `x-amz-server-side-encryption: AES256` header without enforcing encryption, returning a successful `HTTP 200 OK` response.

Requests with this header are now explicitly rejected with an `HTTP 400 Bad Request: InvalidArgument` error, as AES256 server-side encryption is not currently supported by Scaleway Object Storage.

## Solution

Remove the `x-amz-server-side-encryption: AES256` header from your requests. 

## Going further

Refer to the [dedicated documentation](/object-storage/api-cli/enable-sse-c/) for comprehensive information on how to encrypt objects using SSE-C.

- If you did not manage to identify the error and solve it by yourself, [open a support ticket](/account/how-to/open-a-support-ticket/), and provide as many details as possible, along with the necessary information below:
    - Object Storage Endpoint (e.g. `s3.fr-par.scw.cloud`)
    - Bucket name
    - Object name (if the request concerns an object)
    - Request type (PUT, GET, etc.)
    - HTTP status code
    - Date and time (timestamp)
    - User-agent (SDK, client, console, etc.)
    - Transaction ID (if possible)
    - Log / trace of the error (if possible)