So we've apparently had many people report a problem with canceling subscriptions since we upgraded to 2.0. I'm not sure that any of our subscribers have succeeded in canceling their subscription from the cancel link in their email receipt, and we have had to resort to manually deactivating and sometimes refunding them after support requests. I was testing this just now and I am experiencing the same problem, but am unable to pinpoint the problem. The issue does not appear to be happening on our test site (vtdev2.foxycart.com) as was able to successfully cancel a subscription through the email link there. It is only occurring on our live site (secure.verdanttea.com). There isn't much, if any, difference in the configuration of our test and live cart/checkout, so I am not sure what's going on.
When I try to complete the subscription cancellation, the checkout just blanks out and says the cart is empty, and then does not direct to any receipt. On the test site, it succeeds and directs to the receipt. As a diagnostic measure, I added the "not is_subscription_cancel" and "not is_updateinfo" conditions to all of our cart/checkout scripts in the custom footer, but this does not appear to effect the problem.
I will whisper you details for testing this on our live site with a subscription I created. Please take a look at this and get back to me as soon as you can. We'd like to resolve this one promptly if possible. Thanks for your help!