I have loaded and used the ADMIN supplied with Abantecart.  I have logged in and out several times.  Then today it stopped working.  I have not changed anything.  I looked at my files and used
(www)(d0t)mysite(d0t)c0m/abantecart/admin/index(d0t)php as my admin path.  I get nothing back but a 404 error.  I looked at the INDEX.PHP file and I find no difference in all of my copies.

   
<?php
    header('Location: ../index.php');


Before hand, I did do an upload in my phpADMIN using SQL and it reported no errors

I don't know what to do
I want to get back into my ADMIN.

Thanks