The Old ASP.NET Webforms ReportViewer Malfunctions When ClientIDMode Is Static

Environment

Product	Progress® Telerik® Reporting
Version	Q2 2012 and later
Report Viewers	Legacy ASP.NET WebForms Viewer

Description

The described scenario and suggested solution relate to the legacy ASP.NET WebForms ReportViewer. It is recommended that you migrate to the HTML5 ReportViewer.

The old ASP.NET Webforms ReportViewer malfunctions when its ClientIDMode is set to Static.

Cause

The old ASP.NET WebForms ReportViewer has a complex structure and its functionality partially depends on the JavaScript delivered by its HTTP handlers. Setting the ClientIDMode to Static may lead to improper execution of these JavaScript methods.

Solution

To solve this issue, refer to the solutions suggested in the ClientIDMode in ASP.NET 4.0 Web Log blog post by Rick Strahl.