Hi,
If you're using a recent version of HikaShop, the code modification is totally different.
It also depends where you want to change that.
If it's in the order details page for the order status, it's the file "show_general" that you want to edit via the menu Display>views to change the code:
<input type="checkbox" id="data[notify]" name="data[notify]"/>
to:
<input type="checkbox" id="data[notify]" name="data[notify]" checked=checked/>
If it's on the orders listing, it's the file "notification" that you want to edit via the menu Display>views to change the code as explained in my first message on this thread:
www.hikashop.com/forum/4-how-to/15676-se...y-default.html#15677