Wisej.Web.Application.DownloadAndOpen

Dear Team,

I need to download a file from server to client and next delete it from server.

if I use the follow instructions:

Wisej.Web.Application.DownloadAndOpen(“_blank”, SessionFileName, LocalFileName)
IO.File.Delete(SessionFileName)

I get the error: HTTP Error 404.0 – Not Found;
I suppose because the file is deleted before the download is finished.
Any sugget to wait until download is finished and after delete the file?

Thanks in advance