Save modified WordprocessingDocument to new file

If you use a MemoryStream you can save the changes to a new file like this:

byte[] byteArray = File.ReadAllBytes("c:\\data\\hello.docx");
using (MemoryStream stream = new MemoryStream())
{
    stream.Write(byteArray, 0, (int)byteArray.Length);
    using (WordprocessingDocument wordDoc = WordprocessingDocument.Open(stream, true))
    {
       // Do work here
    }
    // Save the file with the new name
    File.WriteAllBytes("C:\\data\\newFileName.docx", stream.ToArray()); 
}