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UpdatePanel Javascript error

Medium Priority
Last Modified: 2012-05-06
Hi experts,
   I use ScriptManager and updatepanel tags, but when insert this components my webpage display javascript error.

attachment webpage code generated and javascript error:
Watch Question

It seems like Sys is not defined correctly!  Maybe set it to System = Sys ????


I just insert the AJAX component for VB.NET.

In the generated code I have identified the error, but I use the same components using C # in another application and I have the same javascript error.

I need to use updatepanel in ASP.NET website using VB.NET, but when I insert the components and reload the page the javascript error is generated
Some of the troubleshooting steps.
1. Check if you have the AJAX Framework installed on your system?
2. Check to see the Script Manager is the first Form element, i.e it should appear before the UpdatePanel or any javascript that accesses Sys.
3. There are many javascript files that you have include and i think a third-party component too.  Check to see if there is any statement that uses the Sys, which needs to be loaded first before they can be accessed.
There can be variety of reasons for this error message though.  You may wish to refer the below link.

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