Excel VBA, SOAP, XML and SharePoint – Verify a File Exists (Updated July 25, 2013)

This last week I have been hard at work on a project for a client.  Essentially, the client needed an excel macro which would accomplish this:

1. Open a worksheet found in a predetermined location on a SharePoint Server.
2. Do some stuff with it.
3. Save the worksheet back to the SharePoint Server.

It seems pretty simple, doesn’t it?  SharePoint is Microsoft, Excel is Microsoft, you’d think the two would talk to each other easily; or that Microsoft would build in various classes and methods associated to make linking Excel to SharePoint simple.