When you upgrade Zen Cart, or any module is always suggested to uninstall the module (from admin) and reinstall to assure that it will work properly.

Quote Originally Posted by wgpeters View Post
I was able to restore my Stripe module, but I have no idea why this worked.
I stumbled on this by trial and error.
Changing the currency in the modules control panel from USD to CAD and then changing it back again restored the payment modules function.
Why this worked or how the upgrade caused it to fail is a mystery, and the only thing I can think of was that I did not take my zencart off-line during the upgrade.