Using your principal, you can build any allowed filename:
private string getfilename ()
{
string dateWithSeconds = DateTime.Now.ToString("MM-dd-yyyy_HH-mm-ss");
string dateWithMinutes = DateTime.Now.ToString("MM-dd-yyyy_HH-mm");
string fullname =_cfg.UserInfo.User.FullName;
return string.Format("{0}_{1}\\{2}", fullname, dateWithMinutes, dateWithSeconds);
}