Had mine, which is the MS Store version, update. Once it was done, the app effecitvely lost itself and no longer functions. Unable to uninstall, unable to reinstall. Data is still intact on drive taking up space.

Currently have PSO2 Tweaker doing a file check to see if I can get it going but this is kinda agitating. anyone have any other ways to get this going again?

This is normally typical of Windows updates. If the game has a loading bar and is grayed out in your start menu, normally a restart would fix the issue. If not, PSO2 Tweaker will definitely help. A tech-saavy person could also delete the old install for you entirely to start fresh with an install of it on Tweaker (you would still be able to use your account that you have been using, so long as you keep GamingServices updated with the MS Store.).

I've been tempted. As it currently stands, it appears the game uninstalled itself, as PSO2 Tweaker reported over 65000 files missing. It's currently downloading them.

Hopefully that gets it up and running again when it's done! Thanks for that information, I wasn't aware that this was a very common issue with the MS STore. I tried to use Steam, but the game won't run at all that way so I don't have a lot of options!