Both Lof and Loc result in a long which has a max value of 2,147,483,647. You would get an error if you try to use one of these functions on a file containing more bytes that this var can hold.

Have a look here
http://www.codeguru.com/cpp/w-d/doc_...cle.php/c12917
and here
http://www.vbforums.com/showthread.php?t=531321