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Add work or school account in Windows 10 or 11 fails with this message: “add account operation is blocked by policy on the device”. Error code: CAA50101
Check the value of Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Policies\Microsoft\Windows\WorkplaceJoin\BlockAADWorkplaceJoin
Change the value to 0.
If this device is managed by your organization, you might not able to change this. Please contact your administrator, if that is the case.