.386
.model flat, stdcall
option casemap:none
include \masm32\include\windows.inc
include \masm32\include\user32.inc
include \masm32\include\kernel32.inc
include \masm32\include\comdlg32.inc
includelib \masm32\lib\user32.lib
includelib \masm32\lib\kernel32.lib
includelib \masm32\lib\comdlg32.lib


.const

  MEMSIZE equ 65535

.data
 
memor DB "d:\file.txt"

file_name DB "d:\file1.txt",0

.data?
hFile HANDLE ?
hMemory HANDLE ?
pMemory DWORD ?
SizeReadWrite DWORD ?
param HANDLE ?   
.code
start:
           
invoke OpenFile,ADDR memor,NULL,OF_READWRITE 

mov param,eax

invoke CreateFile,ADDR file_name,\
                               GENERIC_READ or GENERIC_WRITE ,\
                               FILE_SHARE_READ or FILE_SHARE_WRITE,\

   NULL,OPEN_EXISTING,FILE_ATTRIBUTE_ARCHIVE,\
                                   NULL
                       mov hFile,eax

invoke GlobalAlloc,GMEM_MOVEABLE or GMEM_ZEROINIT,MEMSIZE

                       mov  hMemory,eax

invoke GlobalLock,hMemory

                       mov  pMemory,eax
          
invoke SendMessage,param,WM_GETTEXT,MEMSIZE-1,pMemory

invoke WriteFile,hFile,pMemory,MEMSIZE,ADDR SizeReadWrite,NULL

                       invoke CloseHandle,hFile
                       invoke GlobalUnlock,pMemory
                       invoke GlobalFree,hMemory

end start

.386
.model flat, stdcall
option casemap:none

include \masm32\include\kernel32.inc
includelib \masm32\lib\kernel32.lib

.data

memor DB "d:\file.txt",0
file_name DB "d:\file1.txt",0

.code
start:
	invoke CopyFile, offset memor, offset file_name, 1
	invoke ExitProcess, 0
end start

ML Fatal Error A1000
cannot open file: filename

The assembler was unable to open a source, include, or output file.

One of the following may be a cause: 

The file does not exist. 
The file is in use by another process. 
The filename is not valid. 
A read-only file with the output filename already exists. 
The current drive is full. 
The current directory is the root and is full. 
The device cannot be written to. 
The drive is not ready.