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macbookowner

macrumors newbie
Original poster
Aug 9, 2015
5
1
Hello!
Do You have any idea how it's possible that Mac still remembers passwords to WiFi during reinstallation - after I successfully erased Mac OS Extended (Journaled)? It's really interesting, I thought that erasing disk with Disk Utility means that ALL data will be lost.
 
Last edited:

Significant1

macrumors 68000
Dec 20, 2014
1,622
751
I have Keychain turned off. I'm talking about 7. step of this instruction: https://support.apple.com/en-us/HT201376
Installer automatically connect to my WiFi that I used before erasing computer (secure with password which should be forgotten!)
The system is running from the recovery partition at the time of step 7 and not the partition you erased. So nothing strange in that. It remember from last time you where connected to WiFi in recovery. Most likely when you last installed OSX, since that is where WiFi would be needed.
 

macbookowner

macrumors newbie
Original poster
Aug 9, 2015
5
1
The system is running from the recovery partition at the time of step 7 and not the partition you erased. So nothing strange in that. It remember from last time you where connected to WiFi in recovery. Most likely when you last installed OSX, since that is where WiFi would be needed.
Thanks! It's possible. Does it mean that after I erased partion, OSX still remember some personal information (ex. WiFi passwords) on on the recovery partition?
 

Significant1

macrumors 68000
Dec 20, 2014
1,622
751
Thanks! It's possible. Does it mean that after I erased partion, OSX still remember some personal information (ex. WiFi passwords) on on the recovery partition?
I would not call it personal data. More like configuration used during installation. E.g. interface language, keyboard-layout, network configuration etc.

WiFi password can of course be considered a bit personal.
 

macbookowner

macrumors newbie
Original poster
Aug 9, 2015
5
1
I would not call it personal data. More like configuration used during installation. E.g. interface language, keyboard-layout, network configuration etc.

WiFi password can of course be considered a bit personal.
Thanks. Are there any possibilities to erase Mac completely?
 

Significant1

macrumors 68000
Dec 20, 2014
1,622
751

Weaselboy

Moderator
Staff member
Jan 23, 2005
34,004
15,335
California
Thanks! It's possible. Does it mean that after I erased partion, OSX still remember some personal information (ex. WiFi passwords) on on the recovery partition?

https://support.apple.com/en-us/HT204063

The Internet recovery wifi password is stored in NVRAM (firmware) and no amount of erasing the disk or erasing the recovery partition will get rid of it. After you erase the disk and do the OS reinstall, do a NVRAM reset as described at the above link and the saved wifi password will be erased from firmware.
 
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