From experience don't redirect. Have a landing page which explains that you are out of stock or if the itemis discontinued.
This is quite easy to do, but does take a bit of legwork first.
First create new expanded view product tempates which do not have the buy button include and name them the same as the original but with a generic name at the start. For instance if you have tmp_product.html and tmp_product1.html you could have tmp_tmp_product.html and tmp_tmp_product1.html.
Then in shopexd locate the GetTemplate sub. Directly before the End Sub add in:
if tmpRS("hide")<>False then
template="tmp_" & template
This then causes the product to use your new template of the item is hidden.
Works well and is fairly easy to do.
Hope this helps everyone.
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