Having issues trying to open an excel document on a web form. The excel document is loading via a datatable. This works perfect on my dev pc running the vs2008 web application, but when I try to publish to the web, it gives me an error trying to save the document because it is in use by another program. I've tried using ClosedXML to do this along with the excel interop. Both are having issues because I'm trying to save the document to the server before opening the document. Is there any way to just open a excel document and fill it from a dataset or datatable with out having to save the document first before opening it in vb.net web form?