Uniocode MFC application not able read ANSI encoded text file

FILE *fpRead;
	char *file_buffer;
	if(	(fpRead = _tfopen(strFilePath, _T("rb")) )== NULL)
	{			
		AfxMessageBox(_T("File not open"));
		return;
	}
        fseek (fpRead, 0, SEEK_END);   // non-portable
        unsigned long  size=ftell (fpRead);
        file_buffer=new char[size];
        fread(file_buffer, 1, size, file_buffer);
        CString wfile_buffer;
        wfile_buffer=UTF8toUTF16(file_buffer); //definition stated below, apparently this function is not safe
	AfxMessageBox(wfile_buffer);
        delete file_buffer;
 

CStringW UTF8toUTF16(const CStringA& utf8)
{
   CStringW utf16;
   int len = MultiByteToWideChar(CP_UTF8, 0, utf8, -1, NULL, 0);
   if (len>1)
   { 
      wchar_t *ptr = utf16.GetBuffer(len-1);
      if (ptr) MultiByteToWideChar(CP_UTF8, 0, utf8, -1, ptr, len);
      utf16.ReleaseBuffer();
   }
   return utf16;
}

• Determine the file size.
• Allocate a buffer of that size plus 1 [EDIT]2 bytes[/EDIT] for the terminating NULL character.
• Read the file content into the buffer.
• Terminate the string by setting the last character of the buffer to NULL.
• Determine the encoding of the file.
• If the encoding is UTF-16LE, you can use the buffer as it is.
• Otherwise, convert the buffer content to Unicode (UTF-16LE) using MultiByteToWideChar() (call first with destination buffer and size set to NULL to get the required Unicode string length, allocate the Unicode string buffer, and perform the conversion).
• Delete allocated buffers when not needed anymore (e.g. the file buffer after content has been converted to Unicode).