InvalidRequest - The authorization mechanism you have provided is not supported. Please use AWS4-HMAC-SHA256.
Error
When accessing Amazon S3 buckets that are located in the new AWS Germany (Frankfurt) region, S3Express reports the error "400 - InvalidRequest - The authorization mechanism you have provided is not supported. Please use AWS4-HMAC-SHA256."
Solution
The new AWS signature version 4 is required to access buckets in the new AWS Germany (Frankfurt) region. Please upgrade S3Express to version 1.5.5 or newer. Upgrading is free if you already purchased a license for S3Express version 1, see : www.s3express.com/kb/item29.htm