The Used Mac "Kill Switch": What You Need to Know
Buying a Used Mac: Risks and Hidden Issues
Understanding MDM Lock
- Buying a used Mac can save money but poses risks like iCloud locks, firmware passwords, and degraded components.
- MDM (Mobile Device Management) lock is a significant issue; it prevents access to the device even after reformatting if the Mac was previously enrolled by an organization.
- Once enrolled in MDM, the Mac's serial number is logged in Apple's database, making it impossible to bypass the lock simply by reinstalling macOS.
The Deceptive Practices of Sellers
- Unscrupulous sellers may format the SSD and edit the hosts file to prevent contact with Apple servers, masking the MDM lock until later.
- This deceptive practice allows Macs to function normally for some time but ultimately leads to issues when trying to update or reinstall macOS.
Steps for Buyers
- Always reformat the internal SSD and reinstall macOS immediately after purchase, regardless of seller claims about functionality.
- Check the hosts file using terminal commands (
cat /etc/hosts) to identify any rerouting of Apple server addresses that indicates potential MDM locks.
Seller Honesty and Pricing
- Some sellers are honest about MDM enrollment; they often sell these devices at discounted prices due to their locked status.
Is It Worth Buying an MDM-Locked Mac?
- For most users, buying an MDM-enrolled Mac is not advisable as workarounds are temporary and can lead to ongoing frustrations with updates or security patches.
- Unless you are technically inclined or plan on installing Linux instead of macOS, purchasing such a device may not be worth the hassle.