Can you elaborate on the error? Did you happen to change your security credentials on the AWS S3 side? Either way, you may want to simply create a new access / secret key, Do this from the AWS Console - click on your account in the top right, select My Security Credentials, open up the Access Keys section, and create a new access / secret key pair. Ensure no other systems are using the old pair if you remove it as they will need to be updated. If that does not work, we'll either need to know more about the error or see the logs.