Unicode filename is not supported.

Please add below code to source branch:

in function windows_azure_storage_wp_update_attachment_metadata:

$str = $relativeFileName;
$pos = strrpos($str, ‘/’) + 1;
$relativeFileName = substr($str, 0, $pos) . urlencode(substr($str, $pos));

try {
// Get full file path of uploaded file
$data[‘file’] = $uploadFileName;

// Get mime-type of the file
$mimeType = get_post_mime_type($postID);

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