Known Keep LLCLockbox Address for Checks: Known Keep LLC PO Box 734562 Dallas, TX 75373-4562 17304 Preston Road Suite 800 Dallas, TX 75252 USA (do not mail checks here) 1.800.533.3638 214.414.1986 Fax: 1.800.784.5661 “How Can We Help You Today?”General InquiryRequest Support, Open a HelpDesk TicketRequest a 45 Day Evaluation License