Generating a SSRS report with ReportExecution2005 in VB.net - "The session identifier is missing." Error
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I'm trying to build a function that will generate a report from a Sql Server Reporting Services server in PDF format. I'm using the ReportExecutionService Class. The code is written in VB.NET (.NET framework 2.0). The reporting server is a 2008 one.

The function basically works. For some reports it does generate a PDF file - But for some of the reports it doesn't. 

The error that I get is: "The session identifier is missing. A session identifier is required for this operation." I also included a [link to the XML error output]. 

This is a [link to the method code] that I think is relevant.

Thank you in advance.

[link to the method code]: http://dl.dropbox.com/u/13093445/ssrs_method.vb
[link to the XML error output]: http://dl.dropbox.com/u/13093445/ssrs_error.xml

