Can't Sign In on Xbox Windows App

You can't change a gamertag into a previously owned one but you could sign in to the Windows 10 Xbox app with the old one though.

This link will give you you all the info you need to sign in to the Xbox app on Windows 10.

support.xbox.com/.../signin-xbox-app-on-windows-10

Hi and thanks for reaching Microsoft Xbox gamer's community. My name is Josef.
I'm an Independent Advisor and a Microsoft Xbox user like you.

Hope you're doing great today despite this Samuel

Please try this:

Open Settings, click Update and Security and then Windows Update;

Click Check for Updates;

Click the Download and Install Now option, if available (Install optional updates as well)

Also, check the Microsoft Store for any updates on the Xbox apps and its services and update everything too.

Now, sign out from your account on both Xbox app and Microsoft Store and do this:

Go to windows settings > apps > search for gaming services app > click on it and select advanced options.

After that, click repair and then reset

Then do the same for the Xbox app:

Go to windows settings > apps > search for Xbox app > click on it and select advanced options.

After that, click repair and then reset

Finally do this:

Step 1: Open the Run window by pressing Windows + R key.

Step 2: Input WSReset.exe in the Run window and click OK.

Step 3: Then a command prompt window will appear. After a few seconds, Windows Store will open.

Then do this:

Press Windows button and type Services

On Services App from the list of results, press right-click and run it as administrator

Scroll to the bottom and find the following services:

IP Helper
Xbox Live Auth Manager
Xbox Live Game Save
Xbox Live Networking Service
Gaming Services

And do this with each of the services listed above:

Right-click over the service and select Properties.
Find the Startup type section and make sure it’s set to Automatic (if not, change it to automatic)
If the service isn’t started, click Start to start the services

Restart your PC and finally Sign in again on both Microsoft store and Xbox app with your account and give it a new try

I finally got it to work again. This is what I did:

1. Uninstalled the Xbox app
   
2. Reset the Microsoft store cache with WSReset.exe
   
3. Switched my Windows account to a local account and removed my Microsoft account from Windows
   
4. Restarted the PC
   
5. Installed the Xbox app and started it
   

This led to the usual sign in prompt in the app showing and I could sign in. I think the problem might have been the auto-sign-in feature with Microsoft accounts.

Besides the troubleshooting steps described in your post. What else did you tried?

In that way I can advise you different things or how to proceed

Thanks for the detailed suggestion but this did not solve the problem.