Just taking a wee stab in the dark here, but I'd say that there is something in your server configuration that has disabled the ability for you to use the URL file-access method (Don't you just hate these cryptic error messages) <grin>
Assuming you, like most others, have no way of reconfiguring your hosts servers, the Australia Post module has implemented an alternate method of URL access known as "cURL" (which is why I suggested you make that change).
cURL itself is unrelated to the AustPost module, but it is used for several aspects of zencarts operation, eg, for accepting PayPal payments.
cURL has its own configuration settings.
Some ISP's don't support cURL, but in my experience all ISP's support either one or the other of these two methods.
cURL is supposedly a little more secure than "file".
Anyway, the error message tells us that it is really pointless for you to continue to use the "file" method, so your only hope is to use cURL (which you'll need to configure to get rid of the 'new' errors).
Cheers
Rod




