問題出在你的ReDim語句上，每次你用ReDim改變數組大小時，以前讀進來的數都會被仍掉，所以寫的時候除了最后一個字節都不對。要保留以前讀的數，應該改為： 
    ReDim Preserve a(1 To i) 
    實際上，你可以使用FileLen得到文件長度，這樣程序可以簡化： 
    Dim a() As Byte 
    Open "c:\windows\desktop\flash.exe" For Binary As #2 
    Open "d:\flash.exe" For Binary As #1 
    Dim i As Long 
    i = 0 
    ReDim a(1 To FileLen("c:\windows\desktop\flash.exe")) 
    Do While Not EOF(1) 
    i = i + 1 
    Get #1, , a(i) 
    Loop 
    For s = 1 To i 
    Put #2, , a(s) 
    Next 
    Close 1 
    Close 2 
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