To upgrade the product version, please do the following:
1. Download the latest version of Silverlight Viewer for SSRS here: http://www.perpetuumsoft.com/Downloads.aspx?lang=en&pid=116.
2. Uninstall Perpetuum Silverlight Viewer for SSRS from the client machine using Control Panel->Programs and Features.
3. Reinstall Silverlight Viewer on the client machine.
4. Uninstall Perpetuum Soft Rendering Extension from the server side using Control Panel->Programs and Features.
5. In the following folder '..\Perpetuum Software\Silverlight Viewer for Reporting Services 2008\Reporting Services Rendering Extension\' find the PerpetuumSoft.XamlExtension.msi file, copy it to the server and run. In case you face any problems with installing please have a look at the following article: http://helpcenter.perpetuumsoft.com/KB/a353/how-to-add-rendering-extension-to-reporting-services.aspx?KBSearchID=0.
6. Please make sure that the licenses.licx file exists and contains actual information (if it includes a version number, it should correspond to the version number of the downloaded and installed version). In case you upgrade from version 2.xxx, please have a look at the following article: http://helpcenter.perpetuumsoft.com/KB/a498/licensing-silverlight-viewer-reporting-services-30-versions.aspx.
7. For all projects which use Silverlight Viewer for SSRS, please do Clean and Rebuild (for both, client and server sides).