Microsoft 365 features that help users manage their subscriptions, account settings, and billing information.
Hello Val Peterson,
Thank you for reaching out in Microsoft Q&A forum.
I understand you’re trying to add your self‑built PC to your Microsoft 365 account but it never appears while the others do.
For a device to show up on the Microsoft account page, the Windows sign‑in on that PC must use the same Microsoft account that holds the subscription. If the PC was set up with a local account or a different Microsoft account, the device will not register. The machine also needs to have Windows activated and be signed in to the Microsoft Store with the same account. If any of these are different, the device list will not update. If all conditions are correct and the PC still does not appear, there is unfortunately no additional action available from the user side.
Hope this helps.