Your installation became corrupted which is why you lost all functionality. The best thing to do is to uninstall and reinstall everything using the latest Full Software Solution from http://support.hp.com . Make sure you run the normal USB installation to repair all of the connections and features for you.
Universal Print Drivers are only for printing. They offer no support for scanning. You must use the normal Full Solution to get the scan drivers installed. After that if you really want to use a UPD then you can overwrite the default driver with your specific UPD afterwards. All you should have to do is download the UPD to the machine, kick off the Add a Driver wizard, point it to the UPD folder and let it finish. From there you will have the option to switch your drivers around without having to mess with any ports. The UPD will detect the previous port and take it over for you.
Hope this makes sense, let us know if you have more questions or specific error messages.