Any ideas, folks? I did send in a support ticket and I did search these forums - even tried to post on reddit but was told by mods it wasn't appropriate (even though that's the best place imo for the question). Here's what happened ... ...

Stupid move on my part, but was running out of disk space so tried to copy files over to another drive to run SMITE off that. It didn't work, so I tried deleting and reinstalling the game but got an error message that SMITE was already installed. Did some online research, and looked to uninstall the Hi-Rez Authenticator files, but despite my computer saying they existed via unhidden search, I couldn't find them. It won't let me reinstall the game, and it won't uninstall some files, where they are I have no idea. I'm at a loss and miss playing, would love any troubleshooting tips for Windows 10! Thanks in advance.

EDIT: Also checked the 'Uninstall' registry, and there is NO FILE named hi-rez auth or any other hi-rez file, although I can see it on the Install or Remove settings ... baffling.