客戶固定會寄email給我，內容是一個zip檔。之前都是乖乖的把附件存出來，然後用7z解壓縮，key密碼，存到固定的資料夾。
現在想自已寫一支小程式把這個動作自動化，但卡在解壓縮這一段。我試過用 DotNetZip，發現解出來的檔案名稱會變成亂碼：

底下是程式碼

                using (Ionic.Zip.ZipFile zip = Ionic.Zip.ZipFile.Read(src))
                {
                    // This call to ExtractAll() assumes:
                    //   - none of the entries are password-protected.
                    //   - want to extract all entries to current working directory
                    //   - none of the files in the zip already exist in the directory;
                    //     if they do, the method will throw.
                    string sOutputPath = Path.Combine(Path.GetDirectoryName(src), Path.GetFileNameWithoutExtension(src));
                    //zip.Encryption = EncryptionAlgorithm.WinZipAes256;
                    zip.Password = "xxxxx";
                    zip.ExtractExistingFile = ExtractExistingFileAction.OverwriteSilently;
                    zip.FlattenFoldersOnExtract = true;
                    zip.AlternateEncoding = Encoding.GetEncoding("Big5");
                    zip.AlternateEncodingUsage = ZipOption.Always;
                    zip.ExtractAll(sOutputPath);
                }

也試過用 sevenzipsharp, 但一直卡在
cannot load 7-zip library or internal com error
(試過google大神建議的各種方法，都無解)

請問各位有什麼建議嗎?
(程式碼寫錯，或換個解壓方法，都歡迎討論)

重貼一下最後的程式碼：

                ReadOptions options = new ReadOptions();
                options.Encoding = Encoding.Default;
                using (Ionic.Zip.ZipFile zip = Ionic.Zip.ZipFile.Read(src,options))
                {
                    string sOutputPath = Path.Combine(Path.GetDirectoryName(src), Path.GetFileNameWithoutExtension(src));                    
                    zip.Password = "XXXXXX";
                    zip.ExtractExistingFile = ExtractExistingFileAction.OverwriteSilently;
                    zip.FlattenFoldersOnExtract = true;
                    zip.ExtractAll(sOutputPath);
                }