Windows 10/11 laptops are normally added to a Microsoft account automatically when signing in with that Microsoft account on the device. Manual registration with a serial number is only needed for certain device types (for example, Surface) and can fail if the device type is not supported or the serial number is not accepted.
To check and manage the laptop as a device:
- Sign in on the Acer laptop with the Microsoft account under Settings > Accounts.
- On the same account, go to https://account.microsoft.com/devices and sign in.
- If the laptop is a standard Windows 11 PC, it should appear automatically in the devices list after signing in on the device. If it does, there is no need to add it by serial number.
- If it still does not appear and the site asks for a serial number, use Register device only if the device type is supported (for example, a Surface). If the serial number is not recognized, the device may not be eligible for manual registration.
If the device is managed or owned by an organization (work or school), it cannot be registered to a personal Microsoft account.
If the laptop previously appeared and was removed, verify that the same Microsoft account is used on both the laptop and the devices page, and allow some time for it to sync.
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