Error Message: Exception of type 'System.Web.HttpUnhandledException' was thrown.

 Hi,
I get error on following statement in page_load
hidFileID.Value = Request.QueryString("fid")
 
'Base Exception

'Error Message: Object reference not set to an instance of an object.
 
I see querystring  available, I see hidFileID.value is ""

What can be cause?
Thanks,
Vaibhav Gangal
 
 
 
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