핸들이 비동기 작업을 지원하지 않습니다. 핸들이 중첩된 I/O용이 아닌 동기적으로 열려 있음을 나타내기 위해 FileStream 생성자의 매개 변수를 변경해야 할 수 있습니다.
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English version
Handle does not support asynchronous operations. The parameters to the FileStream constructor may need to be changed to indicate that the handle was opened synchronously (that is, it was not opened for overlapped I/O).
.Net Framework