File upload control enabled false clear the textbox

Hi

I am using File upload control in form.If the user click the inactive radio button all the controls in my form is disabled then click the  active radio button  then enable all the controls.If i enable = false the Fileupload control then enble that control the selected file is cleared .Even i gave the viewstate = true;

What i needs to do?

 

Thanks

Vairam

 

 
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