I just  installed  the Tandy Serial Mouse with my Tandy 1400LT.  I
    ran into a minor problem which may be  of interest to other 1400 users.
    When I installed  the  mouse  and  tried to load the  mouse  driver,  I
    received an error   message  that  the  mouse  wasn't  installed!   The
    solution is obvious but not apparent.

         The problem will occur if you have installed the internal modem on
    your 1400LT.  The 1400 has only one  serial I/O port.  This can be used
    for an RS-232C or the internal modem.  Unfortunately the operative word
    here is "or".

         The solution  is to enter the Setup Mode via CTRL-ALT-INS,  choose
    F4 and select  RS-232C.   You  can now run MOUSE.COM and use the mouse.
    If you try to install the mouse device  driver  (via  CONFIG.SYS) while
    the internal modem is selected, you will NOT get an error message.

         I hope this can help someone else from the frustration  that I ran
    into.  If you  have  any  questions  I will try to be of help.  You can
    send me EMAIL on CompuServe (73727,162) or GEnie (E.DOMBEK).  Good luck
    with your new pet!!!

                                       Ed Dombek    2/25/89