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How to configure Telerik Report Server to use reports with custom functions


Product Progress® Telerik® Report Server


Extending the report engine of the Report Server is not supported out of the box. It requires some manual steps.


  1. Copy the assembly containing the user function(s) in:
    • The bin folder of the Report Server web application, i.e. [Telerik Report Server installation folder]\Telerik.ReportServer.Web\bin (usually C:\Program Files (x86)\Progress\Telerik Report Server\Telerik.ReportServer.Web\bin)
    • for scheduling services only - in the folder of the scheduling service, i.e. [Telerik Report Server installation folder]\Services (usually C:\Program Files (x86)\Progress\Telerik Report Server\Services)
  2. Register the same assembly in the corresponding application configuration files, using the snippets that could be found here.
    • for Report Server web application:
      • in versions up to R3 2018 SP2 ( in [Telerik Report Server installation folder]\Telerik.ReportServer.Web\Web.config (usually C:\Program Files (x86)\Progress\Telerik Report Server\Telerik.ReportServer.Web\Web.config)
      • from version R1 2019 ( in [Telerik Report Server installation folder]\Telerik.ReportServer.Web\TelerikReporting.config
    • for scheduling services only:
      • in versions up to R3 2018 SP2 ( in [Telerik Report Server installation folder]\Services\Telerik.ReportServer.ServiceAgent.exe.config (usually C:\Program Files (x86)\Progress\Telerik Report Server\Services\Telerik.ReportServer.ServiceAgent.exe.config)
      • from version R1 2019 ( in [Telerik Report Server installation folder]\Services\TelerikReporting.config
  3. (optional) If the custom functions are aggregate functions, it would be necessary the Telerik Reporting version used for creating the custom assembly, and the one used in Telerik Report Server to match.
  4. (optional) If Telerik Reporting version on the Report Server is different, add a binding redirect to point the version of Telerik Reporting used to create the custom function in the same way as explained in this help article.
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