if path starts with "\\?\" the ZlpPathHelper.IsAbsolute method returns always false.
var absolutePath = ZlpPathHelper.GetAbsolutePath(longRelativeFilePath, longBasePath);
// absolutePath has prefix \\\\?\\
var isAbsolutePath = ZlpPathHelper.IsAbsolutePath(absolutePath);
//isAbsolutePath is false ;(
if path starts with "\\?\" the ZlpPathHelper.IsAbsolute method returns always false.