I've used my excel file on computer with 32-bits system. Now I have to change system to 64- bits. Unfortunately I have problem with mi macro (I dan't know anything about it - I've just used ready file with it).

When I open the file Microsoft Visual Basic shows:
" The code in this project must be updated for use on 64-bits systems." 

How can I made it?
(Please use simple English - I'm from Poland and I don't speak very well that language)