@Matthias Veelaert , For the error , it seems comes when track Trusted Platform Module (TPM) key attestation, Here, please let us know which mode we choose for Autopilot, user-driven, self-deploying or pre-provisioning?
https://learn.microsoft.com/en-us/mem/autopilot/user-driven
For self-deploying and pre-provisioning mode, virtual machines aren't supported.
https://learn.microsoft.com/en-us/mem/autopilot/self-deploying
https://learn.microsoft.com/en-us/mem/autopilot/pre-provision
Please check the above information and if there's any update, feel free to let us know.
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