I just moved a 1.5.1 Zen-Cart site to a new server (HostGator.)

The following links are generating a 406 error:
Log Out
My Account
Checkout

In the URLs, the template path is visible, ex:
https://www.mysite.com/shop/index.ph...default/common

The server log seems to indicate that the template path is what's causing the error:
Directory not allowed here

Any advice for how to clear these errors up? Thank you in advance!