CultureInfo havoc M/d/yyyy - Cast from string "11/30/2008" to type 'Date'

Hi,

 We have a system which are running for years. Suddenly 1 server is giving problem even though the other servers are running fine. I have checked the REgional setting, Date format M/d/yyyy even the server which is giving problem is SAME setting with other SERVERS.

In global.asax file,  Thread.CurrentThread.CurrentCulture = New CultureInfo("en-us")

also, when i display, Me.TextBox1.Text = CultureInfo.CurrentCulture.Name, it display as "en-US". 

any other setting which i need to look for. the error message is "Cast from string "11/30/2008" to type 'Date' is not valid." 
Operating System : Windows 2003 Server;  DB is SQL server 2000. 


thanks

 
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