Blank page returned when checking out

[Healthadvisor]

Hi,

When customer is checking out and tries to change their shipping address a blank page is returned instead of the change address form.

Here's the link:

https://www.collectiblesforus.com/zcnew/index.php?main_page=checkout_shipping_address[/url]

Zen Cart version is v1.3.9h

Thanks,

[schoolboy]

Go to the cache folder via your FTP, and look inside it for a logged error file.

What error is being logged?