I've got an interesting problem at http://www.herperpro.com
I've done the usual SSL checks, Memory limit etc...and still have the spinning dots on checkout...but only for everyone but me.
When I am logged in, the system calculates the tax just fine (Just setup for Canada tax), and gets over the ajax block just fine. When I register as a new user, even using the same info as I have in my account, the dots do the spin, and no tax line is added....nor is it calculated.
I've got to the point where I've disalbled jquery.blockUI.min.js, and it skips the whole block out, and a user can proceed and buy.
I've checked that the same java scripts are loaded, and the database entries appear to be the same for both users, with respect to billing address.
Any guidance would be appreciated.