CC17 - Nik Software ... I Have The Answer! Yay!

You're lucky. I haven't been able to successfully install Nik filters since CC 2015.0. After losing Nik products with CC 2015.5 I had to revert to CC 2015.0 and haven't updated Photoshop since. Today I had other things on my mind and just clicked "update all" falling back down the rabbit hole. After 45 minutes online with Adobe, including a remote session with a tech support operator (who I had to override as she was about to drag all my Adobe applications to the trash) I've given up and reinstalled CC 2015.0 again. Sure enough, there are all my plugins, working just fine. It's abysmal to be paying for the latest version by subscription but find that Adobe makes no effort to ensure compatibility with a product used by hundreds of thousands of photographers. Not to just bash Adobe, Google's benevolent gesture of buying Nik software, to give it away to the masses, has proven to be nothing but negative IMHO. Their disinterest in updating the software is blatantly obvious. Their purchase of the responsibility for Nik only to abandon the product line is nothing but a disservice to the photographic community.

You Shouldn't need to uninstall the NIK plug-ins.  Just install CC 2017 and run it at least once.  Then reinstall NIK which will find CC 2017, and overwrite the original installation.  Always check the plug-in maker's support pages when having issues around things like Photoshop updates.  They will invariably have the answer.