My website lived on a shared server that my host provider decommissioned last week without realizing that a working site was still on the server. Zen v 1.3.9h has been working on that site for years. The host provider moved my site to a new server (with a new IP address), but since the move I have found that I can no longer use the admin side of my Zen Cart installation. The public portion appears to work correctly.

When I log into Zen Cart Admin, login is successful and the usual admin home page page is displayed. Any activity on that page (links or menu selections) sends me back to the log in screen. This suggests that authentication is working but something else is broken. Names servers and site certificate have been updated. I have cleared my browser cache, cookies and history but the problem persists.

I am at a loss as to where to look for the problem. The web host hasn't responded to a support ticket yet either.