Detected status, means that AMT capability is present, but SCCM is unable to provision it a couple of reasons: already provisioned with a 3rd party console or SMB mode, AMT password changed (Remote Admin of MEBx), etc.
Try the amtopmgr.log to see what's happening and as a test, make a full unprovisioning in one of these machines, better if BIOS allows factory default mode and try the provision process again.
Hi Bruno, i still have quite a few of these machines like this.
reset them all to factory default, removed AD object, certificate and clients came back with the same problem...sccm still says detected, but certificate was issued, AD object created and oobmgmt log says device already provisioned??
seems to be alot of issues with older versions of mebx..pretty much all the newer version of amt provision just fine.