Last Updated: 29 Sep 2020 14:06 by ADMIN
Created on: 23 Sep 2020 04:35
Type: Bug Report
Unable to Preview Report with External StyleSheet in Report Book

Hi there,

Adding an external style sheet to a report in a report-book triggers an error when previewing the report book, "Object reference not set to an instance of an object" 

I've attached the bare minimum project to reproduce the error.

I've also tried upgrading to R3 2020


Posted on: 24 Sep 2020 00:39

Hi Eric,

Thank you for your quick response and acknowledgement of the issue


We'll work with the temporary workaround for now, I appreciate that bugs are a fact of life



Eric R | Senior Technical Support Engineer
Posted on: 23 Sep 2020 20:02

Hi Rick,

Thank you for reporting this. I can confirm the same behavior using the attached sample. As a result, I have converted this to a bug report and renamed it to better describe the bug. Let me go over more details and the workaround below. 


This appears to only be happening during preview of the Report Book in the Standalone Report Designer as the following screenshot displays the styles derived in the external stylesheet. This indicates that the Report, the external stylesheet and the Report Book are still processing successfully.


To workaround this, I recommend using one of our Report Viewers. For additional reference, I have attached a working sample that can be used for previewing Report Books. To run the sample ensure the Telerik NuGet Feed is Configured in Visual Studio.

Wrapping Up

As a token of gratitude, I have awarded your account with Telerik Points. As always, we thank you for your feedback and welcome anymore that you may have.

In the meantime, please let me know if you have any issues with the sample or if you need any additional information. Thank you for being a valued Telerik Reporting developer.


Eric R | Senior Technical Support Engineer
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