Hi @Aleksey Krotov ,
Add the following to <system.web> => <httpHandlers> section.
<add verb="" path="Reserved.ReportViewerWebControl.axd" type = "Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" />
Add the following to <system.webServer> => <handlers> section.
<add name="ReportViewerWebControlHandler" preCondition="integratedMode" verb="" path="Reserved.ReportViewerWebControl.axd" type="Microsoft.Reporting.WebForms.HttpHandler, Microsoft.ReportViewer.WebForms, Version=15.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91" />
Please refer to: ASP.Net: The Report Viewer Web Control HTTP Handler has not been registered in the application's web.config.
The Report Viewer Web Control HTTP Handler has not been registered in the application's web.config file
Best Regards,
Joy
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