问题 I'm trying to download multiple files based on what a user has selected on a form. I have multiple checkboxes in place, so If a user would select Checkboxes 1,3,4 I would want the webclient to download files 1.txt, 3.txt, 4.txt. The WebClient method is causing a "WebClient does not support concurrent I/O operations." error. If chk1.Checked Then WC.DownloadFileAsync(New Uri("http://www.google.com/1.txt), Path.Combine(DataSource & strDirectory, "1.txt")) End If If chk2.Checked Then WC