Hi,
Which ReportViewer are you using? and what ASP framework are you using?
If this is 3.5 framework then:
Is it a:
CrystalReportViewer
or
MicrosoftReportViewer
If you are using CrystalReportViewer there should be no error
but if yor are using MicrosoftReportViewer
then you must add:
<add verb="*" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=9.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a" />
inside
httpHandlers tag in you web.config.
Hope this could help...
Regards,
Algem