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Telerik Report Server

Release History

Progress® Telerik® Report Server R2 2021 SP1 (

June 16, 2021

Keep session alive while the viewer is running

  • Added support for keeping the client session alive in WPF, Windows Forms and HTML5-based report viewers.

What's Improved

  • Added Bring To Front / Send To Back context menu options in Web Report Designer's Explorer Tab, with keyboard shortcuts

What's Changed

  • Report viewers that utilize Telerik Reporting REST service will now keep the client session alive by default


  • "Could not change property 'Name'. Name 'StartPage' already exists." is shown when trying to create second rendering extension with same parameter name of an existing one
  • Drop-down renders incorrect export formats per report until report is not fully loaded

Web Designer

  • Adjacent dynamic groups are not added to the item's group collection
  • Aggregate functions are available for detail values in Table Wizard
  • An error "Value cannot be null. Parameter name: stream" occurs when updating inline CSV or JSON data
  • Creating a new WebService, JSON or SQL data source doesn't add it in the Explorer tree
  • Data source and report section components allow dragging from the Components tab onto the designer surface
  • Dragging a boolean data field from the Explorer tree onto the design surface doesn't set its Value property
  • Graph is not rendered and message is displayed "Grouping expression should not contain aggregate functions." after data source field is moved from Values to Series boxes in the graph wizard
  • JSON data source escapes characters in the source and makes it invalid
  • Rendering setting or parameter cannot be deleted until the report is saved
  • The DataSource's child nodes in the Explorer tree are not draggable
  • The PictureBox item is cropped at design-time if a padding is set
  • Default rendering settings text is visible until report is changed
  • Pop-up windows are not positioned properly
  • Checkboxes styles are incorrect in CSV and JSON data source wizards
  • The font color for displaying the error messages on live-preview items is not set correctly
  • The processing error message is not displayed in the component designer


  • The generated DataMatrix barcodes may not be readable by all barcode readers

Engine Common

  • Swiss QR barcode with combined address does not pass validation due to missing empty lines
  • The null values in the Swiss QR BillData class are serialized incorrectly


  • Freezing table colums and rows headers not working in Firefox and Internet Explorer
  • Frozen column/row headers do not freeze properly when the viewer is in the FitPageWidth scale mode

Telerik Report Server

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