Erase WiFi password stored on recovery partition or firmware?

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Level 2

265 points

Erase WiFi password stored on recovery partition or firmware?

After reformating my internal disk (while booted from an external), I booted from the recovery partition only to find that my Mac still has my WiFi password stored somewhere (it connected to my WiFi network without asking for the password). It thus must be stored either on the recovery partition or somewhere in the firmware (eg, SMC or PRAM).

How can I delete my WiFi password so I can sell it without any personal information on it? I have seen suggestions of resetting the SMC and PRAM but without full confirmation that this really does the trick.

Posted on Jul 12, 2012 5:30 AM

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Answer 1

Shootist007

Level 6

16,709 points

Jul 12, 2012 6:15 AM in response to Sekoya

Well simple, do the SMC and PRAM then check. It's not like you have to take the system apart to do those 2 things.

If you did not Re-Partition the Complete internal drive, you just erased the macintosh HD partition, then the password is stored on the Recovery HD partition which is a separate partition and not visible and won't be touched without a Re-Partitioning of the Physical DRIVE as one partition.

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Answer 2

Sekoya Author

Level 2

265 points

Jul 12, 2012 4:31 PM in response to Sekoya

Resetting the PRAM indeed did the trick. And I did reformat the internal HDD not just erase it. But since resetting the PRAM did remove the WiFi password it definitely was stored in that and not on the recovery partition. Which lets me wonder whether access to my wifi networks would work with the guest account available when using full disk encryption. Or does FDE also encrypt the PRAM?

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