Hi
I was getting this error while working on asp.net 2.0.
Microsoft JScript runtime error: ‘Sys’ is undefined
This error will come mainly due to this reasons
1. If you are using ajax control and if you donot have keep “ajax enabled web confi file”.Then it will throw this error.
To solve this problem, you have to keep ajax enable web confi file like this,you have to add in system.web tag in web confi file
<httpHandlers>
<remove verb="*" path="*.asmx"/>
<add verb="*" path="*.asmx" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
<add verb="*" path="*_AppService.axd" validate="false" type="System.Web.Script.Services.ScriptHandlerFactory, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
<add verb="GET,HEAD" path="ScriptResource.axd" type="System.Web.Handlers.ScriptResourceHandler, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" validate="false"/>
</httpHandlers>
<httpModules>
<add name="ScriptModule" type="System.Web.Handlers.ScriptModule, System.Web.Extensions, Version=1.0.61025.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35"/>
</httpModules>
or you have to remove ajax control from your project.
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Thank you, It took me almost my whole day trying to fix it
I appreciated 🙂
I m glad to know that my artical helped you.
Phew! Thanks for posting this. You saved me from potentially wasting a day trying to fix this “little” issue.
I m glad to know, it helped you