Problem description
The X-Amz-Date form field in the PostObject request is missing.
Causes
The X-Amz-Date form field in the PostObject request is used to identify the signature time. If you initiate a PostObject request that uses the Amazon S3-compatible V4 signature, the x-amz-Date form field is required.
Examples
You initiated a PostObject request that uses the Amazon S3-compatible V4 signature, but the X-Amz-Date form field is missing.
Solutions
Make sure that the X-Amz-Date form field is included in the PostObject request and that a valid value is specified for the X-Amz-Algorithm form field. The format of the X-Amz-Date form field is yyyyMMddTHHmmssZ.
For more information, see PostObject.