Within Microsoft, there is a web service already implemented that I can use in my solution to call the bug tracking system and get back the data described in the previous article.  For my demo, I’m going to implement a demo web service that will stand in for that internal Microsoft web service.  It will return the same basic data structures as the internal web service does, so when I run my own copy of VSTO bug tracker, I can swap out this demo web service for the real one. The demo web service will have three web methods.  The first method is called BulkDataExport.  This method takes a start date and an end date and returns back a dataset with all the bug data for that time period.  This is a simplified version of the Microsoft provided web service that I use internally.  That web method has more parameters to specify milestone, release, team, etc.   But I will omit those for simplicity since my data is specific to my team. <WebMethod()> _ Public Function BulkDataExport( ByVal dateFrom As String , _ ByVal dateTo As String ) As System.Data.DataSet [WebMethod()] public System.Data.DataSet BulkDataExport( string dateFrom, string dateTo) The second method is called to get one particular bug stat value for one particular date.  This will be used by the UDF I will write later.  This takes a particular team (milestone and release I omit) as well as the name of the column I want to retrieve (e.g.

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2. VSTO Bug Tracker : The Web Service