Getting error while trying to expand/collpase treeview node C#

See more:

.NET1.1

C#2.0

.NET3.0

C#3.0

C#

, +

Am getting below error while trying to expand/collapse the tree view.


Webpage error details

User Agent: Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; .NET4.0C; .NET4.0E; InfoPath.3; MS-RTC LM 8)
Timestamp: Wed, 12 Mar 2014 13:59:14 UTC


Message: 'ctl00_m_g_c57161b9_37b7_446b_817a_6255640f9f71_ctl01_Data' is undefined
Line: 1
Char: 1
Code: 0
URI: https://team.cill.com/sites/ Ftest/Pages/empl.aspx

What could be the reason?
how to solve this?

Anyone faced these kind of issues?

Note: Am working on sharepoint webparts project,Tree view is one of the control in my webpart.Am able to do this in my local but getting error in server.This is javascript.