FindFirstFile and FindNextFile crash my program in assembly. Why? - file

Question

I am writing a program that looking for files with the extension ".fly". It displays the names of the founded files, but when I try to use FindFirstFile and FindNextFile, my program crashes. I have tried with FindFirstFileA (ANSI Version of the function) , but my code crashes too. Please, give me a example of code if it's possible.
Please, thanks for your answers. Here's my source code written in FASM Assembly
format pe console 4.0
include 'C:\fasm\INCLUDE\WIN32AX.INC'
; Declare a macro to make buffers
macro dup label,lcount
{ forward
label#:
common
repeat lcount
forward
db 0
common
end repeat }
.code
main:
explore_directoy:
invoke FindFirstFile,file_extension, FIND_STRUCT ; find the first *.fly
mov dword [find_handle], eax
find_more_files:
cmp eax, 0
je exit
call show_file
findnextfile:
invoke FindNextFile, dword [find_handle], FIND_STRUCT
jmp find_more_files
show_file:
invoke MessageBox, NULL, addr msg, addr msg_caption, MB_OK ; Easy way of outputing the text
;invoke MessageBox, NULL, addr cFileName, addr msg_caption, MB_OK
ret
exit:
invoke ExitProcess, 0
datazone:
end_msg db 'End of program', 0
msg db 'File founded', 0
msg_caption db 'Assembly program...', 0
file_extension db '*.fly', 0
find_handle dd 0 ; handles/other stuff..
FIND_STRUCT: ; find structure used with searching
dwFileAttributes dd 0
ftCreationTime dd 0,0
ftLastAccessTime dd 0,0
ftLastWriteTime dd 0,0
nFileSizeHigh dd 0
nFileSizeLow dd 0
dwReserved0 dd 0
dwReserved1 dd 0
dup cFileName, 256 ; found file buffer
dup cAlternate, 14
.end main

Answer 1

Your .text section isn't writable. Change
.code
to
section '.text' readable writable executable

Answer 2

Data should go into the .data section, not the .code section. If your assembler supports uninitialized data (all values defined as ?), then it should go into the .data? section (this is the equivalent of a bss (block started by symbol) section used in some other assemblers).