下载zip文件ASP MVC时出现问题

我正在使用将某些文件压缩在一起的ASP MVC网站。它似乎正在工作，但是当我尝试提取文件时，我得到了

An unexpected error is keeping you from copying the file. If you continue the receive this error, you can use the error code to search for help with this problem.
enter code here


Error 0x80004005: Unspecified error

7 Zip表示CRC失败。文件已损坏。

似乎在编写或下载zip时东西已损坏。我尝试了2种不同的方法来下载具有相同结果的文件。

public ActionResult DownloadFiles()
{
    List<string> files = GetFileList();
    using (ZipFile zip = new ZipFile())
    {
        foreach (string file in files)
            zip.AddFile(file, string.Empty);

        MemoryStream output = new MemoryStream();
        zip.Save(output);
        return File(output.ToArray(), "application/zip", "file.zip");
    }
}

public void DownloadFiles()
{
    List<string> files = GetFileList();
    using (ZipFile zip = new ZipFile())
    {
        foreach (string file in files)
            zip.AddFile(file, string.Empty);

        Response.Clear();
        Response.BufferOutput = false;
        Response.ContentType = "application/zip";
        Response.AddHeader("content-disposition", "attachment; filename=file.zip");
        zip.Save(Response.OutputStream);
        Response.End();
    }
}

<button onclick="fn_DownloadFiles()">Download Selected</button>

function fn_DownloadSelectedFiles() 
{
    window.location.href = "/Files/DownloadFiles"
}

文件为什么会被损坏？

我也尝试过

public ActionResult DownloadFiles(string filePaths)
{
    List<string> files = GetFileList();
    using (MemoryStream zipStream = new MemoryStream())
    using (ZipArchive zipArchive = new ZipArchive(zipStream, ZipArchiveMode.Create, true))
    {
        foreach (string file in files)
        {
            ZipArchiveEntry entry = zipArchive.CreateEntry(file, CompressionLevel.Fastest);

            using (FileStream fileStream = new FileStream(file, FileMode.Open, FileAccess.Read, FileShare.ReadWrite))
            using (Stream entryStream = entry.Open())
                fileStream.CopyTo(entryStream);
        }
        return File(zipStream.ToArray(), "application/zip", "files.zip"));
    }
}

这样我得到Windows无法打开该文件夹。压缩（压缩）的文件夹无效。