Hi there,
This problem can be caused by a lack of communication between the Windows HLK Controller computer and the Windows HLK Client computer, or by a trusted key mismatch between the two systems.
Run a quick check on these points
(1) Move the machine in Machine Pool to default pool.
(2) Delete the machine moved to the default pool.
(3) Restart the HLK Client OS of the deleted machine.
(4) Since the machine appears in the default pool, move the machine to Machine Pool.
(5) Set the machine moved to Machine Pool to Ready.
Troubleshooting Windows HLK Client
https://learn.microsoft.com/en-us/windows-hardware/test/hlk/user/troubleshooting-windows-hlk-client
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