Problems with Microsoft.ReportingServices.ReportViewerControl.WebForms

Question

Hello,
we use a WebForm on our site for the reports. After migrating our servers, a strange message suddenly appears under the parameters.

Furthermore, we sometimes get the error with the parameter dropdowns:

Reserved.ReportViewerWebControl.axd?OpType=Resource&Version=15.0.1484.0&Name=ViewerScript:1   
          
       Uncaught TypeError: Cannot read properties of null (reading 'style')  
    at Microsoft.Reporting.WebFormsClient._MultiValueParameterInputControl.ToggleFloatingFrameVisibility (Reserved.ReportViewerWebControl.axd?OpType=Resource&Version=15.0.1484.0&Name=ViewerScript:1:45927)  
    at Microsoft.Reporting.WebFormsClient._MultiValueParameterInputControl.OnDropDownImageClick (Reserved.ReportViewerWebControl.axd?OpType=Resource&Version=15.0.1484.0&Name=ViewerScript:1:45324)  
    at HTMLButtonElement.<anonymous> (ScriptResource.axd?d=adh3E5cO-su6kssCIGU3RIsaBrOaFhZ5COMZYONjKvMLkoP-bkwEkf6A8rU5Ukv6uo2Ut26Ql8Lt_j2ZNy5kOb5V3PJwvVu8FwPjs6F4ddvNysqp9k2IPQ7mJ3OMRrrDyOxtxosKzstODyTHOKWOWGkHet4EuXX85-mEBgAYNsk1&t=49337fe8:5:307)  
    at HTMLButtonElement.b (ScriptResource.axd?d=adh3E5cO-su6kssCIGU3RIsaBrOaFhZ5COMZYONjKvMLkoP-bkwEkf6A8rU5Ukv6uo2Ut26Ql8Lt_j2ZNy5kOb5V3PJwvVu8FwPjs6F4ddvNysqp9k2IPQ7mJ3OMRrrDyOxtxosKzstODyTHOKWOWGkHet4EuXX85-mEBgAYNsk1&t=49337fe8:5:57482)  

We updated NugetPackage to the latest version.

Does anyone have an idea what the cause can be or how the errors and problems can be fixed?

Answer 1

Hi @Stefanie Ewald ,
Did the report viewer work fine before you migrated the server? Do your reports work properly in the web portal?
Judging from your error message, it is possible that your report viewer configuration has changed or the property is empty, so that the read property data cannot be found.
Best Regards,
Joy