ASP Source

rs.Save Response, adPersistXML

rs is an ADODB.RecordSet variable, and its result is being written to the ASP Response

Wrong Migration

rs.Save(Response <-- The ASP.NET Response is not COM, ADODB.Recordset is a COM object, ADODB.PersistFormatEnum.adPersistXML);  

 So we cannot write directly to the ASP.NET response. We need a COM Stream object

Solution

ADODB.Stream s = new ADODB.Stream();

rs.Save(s, ADODB.PersistFormatEnum.adPersistXML);               

Response.Write(s.ReadText(-1));

In this example an ADODB.Stream object is created, data is written into it and the it is flushed to the ASP.NET response