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A 0x800a139e JavaScript Runtime Syntax Error Occurs


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When you run a Telerik UI project in the debug mode under Internet Explorer, the Visual Studio output window may throw JavaScript errors.

Error Messages

Exception was thrown at line 1577, column 10673 in http://localhost:55082/TWS/Telerik.Web.UI.WebResource.axd?_TSM_HiddenField_=RadScriptManager1_TSM&compress=1&_TSM_CombinedScripts_=;;System.Web.Extensions,+Version=,+Culture=neutral,+PublicKeyToken=31bf3856ad364e35:en-US:0f2ae90c-87fb-4f74-9210-4b167170d85e:ea597d4b:b25378d2;Telerik.Web.UI,+Version=2016.3.1027.40,+Culture=neutral,+PublicKeyToken=121fae78165ba3d4:en-US:a5034868-8cfd-4375-ba8c-d3e7543c32f7:16e4e7cd:f7645509:24ee1bba:4cd1fec6:77613e24:71188da4:f0c58c30:9b7cc2d2:ec7335e:d944e0f6:c442ac3f:8d1fecce:69667591:6b6b9ee5:595e7652

0x800a139e - JavaScript runtime error: SyntaxError

Steps to Reproduce

The issue can be reproduced on a simple page with no Telerik controls that contains a reference to jQuery. The following example demonstrates the Visual Studio output window showing JavaScript errors when a project that references jQuery is run in the debug mode under Internet Explorer.

<form id="form1" runat="server">
<asp:ScriptManager ID="Scriptmanager1" runat="server">
<asp:ScriptReference Path="~/Scripts/jquery-1.9.1.js" />

As a result, the Exception was thrown at line 4224, column 4 in http://localhost:60537/WebSite1/Scripts/jquery-1.9.1.js is thrown and the 0x800a139e - JavaScript runtime error: SyntaxError error occurs.


The issue is not directly related to the Telerik UI for ASP.NET AJAX controls.


The runtime error is from a caught exception that doesn't affect the production environment. For more information, refer to this bug report.

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