Last Updated: 19 May 2021 10:59 by ADMIN
Created on: 07 Apr 2021 13:34
Type: Bug Report
Upgrade Wizard Breaks Script Reference


I create an ASP.NET Web Application - Empty. I add to it a Telerik HTML Report Viewer page. The wizard creates a new REST service with a sample report. Inside the Html5ReportViewer.html file is the line

<!--If Kendo is used it should be added before the report viewer.-->

 <script src="/api/reports/resources/js/telerikReportViewer-"></script>


with a trailing / in the src attribute. This works perfectly.


I have a ASP.NET Webforms website that displays reports from the Reporting web application.  Pages that display a report also have this script tag. However, any time there is an update for the Reporting toolkit, if I use the Reporting Upgrade Wizard, (Visual Studio 2019 "Extensions" menu -> Telerik -> Reporting -> Upgrade Wizard) the script tags get updated with the latest version, but the trailing / in the src attribute is no longer there and the page breaks because the Javascript library is not loaded. Adding in the / fixes the problem.  Is this intended behavior or a bug in the upgrade wizard?


Posted on: 19 May 2021 10:59

Hi Todd,

Thank you for the video. Now the problem is clearer.

I tested with our CSharp.NetFramework.WebFormsIntegrationDemo and the CSharp.NetFramework.Html5IntegrationDemo and confirm that when there was a version specified, the Upgrade Wizard deleted the trailing slash after updating the version in the reference. The trailing slash wasn't removed though when the version was not specified, as in our demos.

The reason for this is that generally, the trailing slash is redundant. I suspect that your application is set up to search for the resource in the file system rather than from the service if there is no trailing slash.

I have approved the bug report and associated it with a work item in our system. As a token of gratitude, we have updated your Telerik points.

Meanwhile, you may try to change the settings of the system/application to associate the URLs without trailing slash also with service requests. The other workaround could be to remove the '-version.min.js' from the URL so that the Upgrade Wizard doesn't change it.

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Posted on: 12 May 2021 14:38

An update to the Telerik tools was available today, so I was able to make a video of what I experience. (2min 53sec long)

I couldn't create a video that was less than 20MB so I uploaded it to YouTube.



Posted on: 14 Apr 2021 09:05

Hello Todd,

I tested to upgrade our demo with an older version. Here is a link to a silent video with my test. Note that the leading slash was not removed by the Upgrade Wizard. I made some changes in the code due to the breaking changes we introduced between the versions I used.

I tested also with a newly created empty ASP.NET project and the slash wasn't removed when the version of the viewer changed from older to newer or vice-versa.

I was not able to reproduce the described behavior and for that reason, I will decline the bug report.

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