Hi @Vojtěch Novotný,
Thanks for reaching out to Microsoft Q&A.
Error 8018000a seems to be "The device is already enrolled"
Cause: One of the following conditions is true:
- A different user has already enrolled the device in Intune or joined the device to Microsoft Entra ID. To determine whether this is the case, go to Settings > Accounts > Work Access. Look for a message that's similar to "Another user on the system is already connected to a work or school. Please remove that work or school connection and try again."
Solution:
Use these steps to remove the other work or school account.
- Sign out of Windows, then sign in by using the other account that has enrolled or joined the device.
- Go to Settings > Accounts > Work Access, then remove the work or school account.
- Sign out of Windows, then sign in by using your account.
- Enroll the device in Intune or join the device to Microsoft Entra ID.
- registry, read How to back up and restore the registry in Windows
- Error 8018000a: The device is already enrolled.
- Error 8018000a: "Something went wrong. The device is already enrolled. You can contact your system administrator with the error code 8018000a." Cause: One of the following conditions is true:
- A different user has already enrolled the device in Intune or joined the device to Microsoft Entra ID. To determine whether this is the case, go to Settings > Accounts > Work Access. Look for a message that's similar to "Another user on the system is already connected to a work or school. Please remove that work or school connection and try again."
- Sign out of Windows, then sign in by using the other account that has enrolled or joined the device.
- Go to Settings > Accounts > Work Access, then remove the work or school account.
- Sign out of Windows, then sign in by using your account.
- Enroll the device in Intune or join the device to Microsoft Entra ID.
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