string[] filePaths = Directory.GetFiles(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData) + "\\capture\\capture");

using (ZipArchive zipFrom = ZipFile.Open(filePaths1[c], ZipArchiveMode.Read))
using (ZipArchive zipTo = ZipFile.Open(filePaths1[c] + ".tmp", ZipArchiveMode.Create))
{
    foreach (ZipArchiveEntry entryFrom in zipFrom.Entries)
    {
        ZipArchiveEntry entryTo = zipTo.CreateEntry(entryFrom.FullName);

        using (Stream streamFrom = entryFrom.Open())
        using (Stream streamTo = entryTo.Open())
        {
            streamFrom.CopyTo(streamTo);
        }
    }

    foreach (String filePath in filePaths)
    {
        string nm = Path.GetFileName(filePath);
        zipTo.CreateEntryFromFile(filePath, "capture/" + nm, CompressionLevel.Optimal);
    }
}

File.Delete(filePaths1[c]);
File.Move(filePaths1[c] + ".tmp", filePaths1[c]);