Under Review
Last Updated: 17 Feb 2021 13:38 by ADMIN
Ikbum Kim
Created on: 23 Jul 2020 01:41
Type: Bug Report
The HTML5 Report Viewer error "Error shown. Throwing promises chain stop error." is not informative

I am currently using Reporting
The following error occurred while using Reporting.

'Non-Error promise rejection captured with value: Error shown. Throwing promises chain stop error.'

I looked up the cause of this error, and I was able to confirm the following article.


As explained in the above article, the error in Report Server ( has been corrected to appear to be a significant error.

So I looked up the release note to see if this error was fixed in the Reporting product, but I couldn't find any related information.

Is this error corrected on the Report Server only and not corrected in Reporting? If so, when can it be revised?

Posted on: 17 Feb 2021 13:38

Hello Omti,

You can test the following options:

- use Fiddler to check for any failing request. You may send us the SAZ file, so we can inspect it on our end;

- check if there are any errors in the console of the browser;

- attach Trace Listener and inspect the generated log file which you can also send us;

Useful information can be also found in Improve Your Debugging Skills with Chrome DevTools Blog post.

Note that we always recommend upgrading the Telerik Reporting ( and the Telerik Report Server to the latest versions (

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Posted on: 15 Feb 2021 05:21

Hello Elena,

You told me, "I suggest you inspect the requests that the viewer is making (to see whether there are some errors) and debug the issue based on this information.".

How can I inspect the requests?

I'm getting the error still now. But I don't know what is the problem.

Could you tell me the way that debugging the issue?


Posted on: 28 Jul 2020 13:01

Hello Ikbum,

The issue is not in the Report Server or Reporting but rather the HTML5 Report Viewer which is used by both. The feature request you have found is incorrectly named and categorized as a Report Server problem and that is why you have been misled. 

To answer your question directly - no, it hasn't been fixed. The fix described here is incomplete and scoped for a single scenario and we would need to revisit the error logging of the viewer once again. That is why I have reopened the case and we will fix the problem as soon as possible.

However, the bug is not critical or blocking. We can address the issue you're experiencing right away. This error can occur, for example, while the report is created, the document info is requested, the parameters or the pages are loaded, etc. Therefore, I suggest you inspect the requests that the viewer is making (to see whether there are some errors) and debug the issue based on this information. If no failing requests exist, I would suggest you send us the report so that we can reproduce the error locally and try to find a solution.

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Ikbum Kim
Posted on: 28 Jul 2020 08:58
In other word, Is "Error shown. Throwing promises chain stop error." fixed in Reporting?
Ikbum Kim
Posted on: 28 Jul 2020 08:28
You seem to have misunderstood my question. What I am using is Telerik.Reporting (ver, and what I read is Report Server (ver
I know that Reporting and Report Server are different products.

My question is to confirm that the bug modified in Report Server R2 2019 SP1 has also been modified in Reporting.

If it has been modified, please let me know which release note it is in.
Posted on: 23 Jul 2020 11:08

Hi Ikbum,

Thank you for reporting this issue. I went through the changeset from R2 2019 SP1 and saw that the fix is scoped to cases when the response from the service contains some meaningful exception message. However, your case is obviously not such and we would need to enhance the error logging further. I will make this thread public and set its status to a Bug Report.

In the meantime, could you please try to reproduce the issue and check (in the browser's developer tools or Fiddler) which request is failing? 

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