Forza Horizon 5 not starting on Windows 10( xbox launcher/ms-store | error code: 0x12c)

Forza cannot be opened anymore (the error popup window redirects to the ms-store which forza cannot be opened from either), and the xbox launcher won't launch. Microsoft Store looking for updates runs forever.

UPDATE:
I reinstalled Xbox GameServices and now the game starts again with the error code 0x12c as before

Forza technical support usually takes few days to respond, if you have opened a ticket it is a matter of waiting for a response.

Also you can try to perform a system reset, you can do this while keeping your files.

If you are on Windows 11:

Select Start > Settings > System > Recovery > Reset this PC.

Then make sure you have the option to keep your files enabled.

Keep my files > Change settings > Pre-installed apps On.

If you are on Windows 10:

Select the Start button, then Settings > Update and security > Recovery. Under Restore this PC, select Get Started and then verify that the Keep your files option is active.

This is very interesting. I checked and only found the following services in the list:
XboxGipSvc

XblAuthManager

XboxNetApiSvc (Xbox Live Networking Service)

XblGameSave

Microsoft Store InstallService

Gaming Services

I put them on automatic startup. But the rest of the services you mentioned are missing (Game Bar, Xbox TCUI)

UPDATE:

I rebooted my PC and the game returns same error after approx 1:30min

Use the Windows search engine and type "PowerShell", Then run it as administrator.

On the Administrator Windows PowerShell screen, type the following command and press Enter:

get-appxpackage Microsoft.GamingServices | remove-AppxPackage -allusers

In the same window, type the following command and press Enter:

start ms-windows-store://pdp/?productid=9MWPM2CQNLLHN

In the Windows search bar type "Services".

Scroll to the bottom and find the following services: XblAuth Manager, XblGameSave, XboxGipSvc, Xbox Live Game Save, Xbox Live Networking Service, Microsoft Store Install Service, GamingServices, Game Bar, Xbox TCUI and any service with "Xbox" in its name.

Right-click on the service (you must do this for each of them) and select Properties .

In the Startup Type section of the "General" tab, make sure it is set to Automatic . If it is not already started, click Start.

Then click Apply and OK to save the changes.

Restart the device and try again.

Open the Registry Editor, locate these paths and delete them

HKEY_LOCAL_MACHINE_LOCAL_MACHINE_SYSTEM_CurrentControlSet\Set\Services\GamingServices

HKEY_LOCAL_MACHINE_LOCAL_MACHINE_CurrentControlSet\Services\GamingServicesNet

Restart the PC, open the Microsoft store and go to your library, then go to check for updates.

This will cause an application to download, this may take a while.

Once installed, restart the PC again and repeat the process again to check for updates. After this try your download.