Loading
Upcoming Mandatory Changes to Public Key Infrastructure (PKI)Read More
Salesforce Enforces New Security Requirements in Summer 2026Read More

Resolving Amazon S3 (403) Errors in dataloader.io Tasks

Publish Date: Jun 30, 2026
Description

Issue

When running your dataloader.io from MuleSoft task, it fails with one of the following errors:

 

  • Forbidden (Service: Amazon S3; Status Code: 403
  • Error Code: 403 Forbidden; Request ID: 6MA4BWN7615EPXJF
  • The request signature we calculated does not match the signature you provided. Check your key and signing method. (Service: Amazon S3; Status Code: 403)
  • Error Code: SignatureDoesNotMatch; Request ID: #############

Cause

The error from the title occurs when the task name contains any special characters. This started happening after an internal update that changed the encoding.

 
Resolution

To avoid the Forbidden error code 403 errors, please, edit your task name replacing any special characters and keeping only numbers, letters and spaces. Avoid also using accent marks or any similar symbol and keep just plain letters. Characters like á, ñ, ç or any other similar character will produce the error.

Knowledge Article Number

005318739

 
Loading
Salesforce Help | Article