How can I open a file on the user's machine from the backend in C#.Net WebPages?

Question

In my web-app (WebPages, C#.NET) I have a drag and drop file box where user's can drag files from windows explorer and, once dropped, it will save in a given location on a shared drive. This part is working fine. The box looks something like this:

The problem is, that it also reads files from the same directory and my user's would like to be able to open the files from this interface on dblclick. I have written an ajax request with jquery (the ajax, too, is working fine), but I can't seem to get the files to open on the user's machine no matter what I try.

Most references I try and look up point me towards System.Diagnostics.Process.Start(@"<directory goes here>") but this doesn't really do anything. It will open some process on the server side, but nothing opens, either on the server or on the user's machine.

What they'd like to do, for instance, is double click 'Hazcom.xls' and it would use the default associated application to open the file. In this case, of course, Microsoft Excel.

Is this even possible or am I chasing a wild goose here?

Sources I've Tried:

• Open file with associated application
• http://www.csharp-examples.net/open-file-with-default-application/
• How can I open Windows Explorer to a certain directory from within a WPF app?
• c# open file with default application and parameters

There have been a few more sources I've tried, as well, but they're all pretty much in the same vein as these.

Additional Info:

• The internal Intranet application runs on a server using IIS 8
• The solution is desired to be opened on the user's machine and not, say, the server itself.
• The path to the files is dynamically changing depending on what they have loaded into the interface.
• Though, I'm not expecting this to be a solution viable for client side (jquery) I'd be happy to look into that if that's the only solution available.
• I'd also settle for simply opening the file location, instead of the actual file itself, but I've had no luck with this either, for what looks like the same reasons as the original problem.