Paypal Express doesn't save settings

I've just tried to enable the PayPal Express module in a new installation of OpenCart, and every time I enter the API username, and other details, upon saving the changes I am redirected to the dashboard/admin home page, and the module settings are not saved, and it's still disabled.

This doesn't happen with any of the other modules.

I'm also getting this error:

yes because paypal express does not show in the admin because its not finished. you must have renamed the file to get it to appear.

either that or he got it from Q and most likely has an old version if that's the case.

Nah.. my mods always work