Need help with Microsoft Store / Xbox App on Windows 10 - not downloading games - Xbox App...

This is my first post, but I feel like I've been here for a while.

I have a new Win10 pc. I'm a long-time subscriber to Game Pass on console, but recently decided to try it on PC to enjoy Flight Sim and some other MS exclusives.

I subscribed to Game Pass for PC, and downloaded the Xbox App. The app opens fine, links right up to my account, but when I browse the catalog and select a game to Install, the Xbox App does not list my hard drives. I have 2 drives. Instead, it says " () Available Unknown". In the Xbox App, when I click my profile, then general, I see the area where I can direct the app to install games, but it also has a dropdown menu with no options.

I called support. They had me try to go through the Microsoft Store. Sweet, I can see all the gamepass games. I click on download there, it shows my drives! I select my drive, click install, and, it does nothing. No errors, it just doesn't add the game to my queue or begin installing.

Things I've done to fix:

- At first, my Microsoft Store App was unable to download anything due to error code 0x00000000. That seemed to clear up as I took some of the steps below, yet here I am still unable to use the subscription.

- Repaired Xbox App and Store app.

- Ran all associated troubleshooters.

- Reset store app cache using wsreset.exe command

- Deleted and reinstalled game services numerous times

- Deleted and reinstalled Xbox app numerous times.

- Deleted and reinstalled Microsoft Store numerous times.

- Checked for updates via Update and Security feature, I'm all up to date.

- Followed the Xbox App banner to try to download KB5004476. I found the correct update for my OS x64 but can't apply to system as I get error message that it isn't applicable.

- followed other MS Community posts about deleting registry entries for gamingservices and gamingservicesnet. Followed all those steps exactly with no luck.

- Downloaded a whole fresh install of Windows 10.

- Spoke to Windows Support and Xbox Support. Both recommended repeating steps I've already taken many times over.

So, where do I go from here? The Xbox agent was suggesting it's a HDD issue but I refused that notion. I have Steam, and Epic, and Ubisoft apps that have no problems seeing my HDD's and downloading games.

Any advice is appreciated. It's late so I'll likely reply tomorrow with any updates.

:)