Custom Http Handlers IIS7 and ASP.NET

We have some HTTP handlers specified in our web.config. When we were running this site via a Web Site Project, all worked fine. But for some reason, after porting this over to a WAP project and pointing to the .NET 3.5 framework, the handlers are not working when I bring up the site in IIS 7 on our dev box. Do I need to do something special in IIS7 other than the specified custom handlers that already exist in my web.config?

Access is denied at System.Diagnostics.Process.StartWithCreateProcess(ProcessStartInfo startInfo)

I am trying to upload files and convert them to another format before saving them on my web server, but I get the following error:
System.ComponentModel.Win32Exception (0x80004005): Access is denied at System.Diagnostics.Process.StartWithCreateProcess(ProcessStartInfo startInfo) at System.Diagnostics.Process.Start()

Session Variables not saved when page is in an iFrame

I have an aspx page with a listbox control. The listbox is populated from a collection that is retrieved from a service when the page loads. When the user selects an item from the listbox the page posts back, adding the retrieved objects to the session before reloading. On the reload I use the session objects instead of having to call the service again.