Reset user password on OS X 10.8 Mountain Lion

OS X 10.8 Mountain Lion allows for easy password recovery via the Recovery HD partition installed on any 10.8 system. Here is how to reset your password:

1. Boot into the Recovery HD partition by holding Command-R during boot and before the Apple logo appears.
2. After the Recovery boot is complete, Choose Terminal from the Utilities menu.
3. Type “resetpassword” at the Terminal prompt and press return.
4. Choose your system disk (f.e. “Macintosh HD”) and the user account to reset the password for.
5. Enter the new password and hit the Save button.
6. Restart.

Clear DNS cache on OS X 10.8 Mountain Lion

Historically, the Directory Services were responsible for DNS queries and caching on Mac OS X 10.5 and earlier. Back then, to clear the DNS cache one would issue the “dscacheutil -flushcache” command. With the further development of various services based on the multicast DNS a mDNS service fully took over both unicast and multicast DNS queries and response caching on later OS X versions.

While the “dscacheutil” is still there even on OS X 10.8 Mountain Lion, it won’t reset the caches properly. The correct method to clear DNS cache on 10.7 and 10.8 is to restart the mDNS service, “mDNSResponder”:

sudo killall -HUP mDNSResponder

If this doesn’t seem to help, try reloading the service:

sudo launchctl unload /System/Library/LaunchDaemons/
sudo launchctl load /System/Library/LaunchDaemons/

Moving Apple Mail settings from computer to computer on OS X 10.8 Mountain Lion

The location has changed since Mountain Lion is out, now the Apple Mail settings reside in:


The Mail messages, rules and Notes are still in the old location:


Just copy the contents to your new computer, and you are done!

Updated fix for “Still waiting for root device” on OS X 10.8.2 Mountain Lion

Apple’s OS X Mountain Lion update to 10.8.2 has modified the IOAHCIFamily.kext once again, resulting in a failed boot with the “Still waiting for root device” error on the console. The previous fix won’t work, as well.

Here is the updated fix for 10.8.2’s version of IOAHCIFamily.kext. Don’t copy-paste everything into the Terminal at once, do it one line at a time. Pasting the whole code at once will result in the second half of the commands being used as your password at the first sudo command.

The following commands place a backup of the unmodified binary before patching it.

cd /System/Library/Extensions/IOAHCIFamily.kext/Contents/PlugIns/IOAHCIBlockStorage.kext/Contents/MacOS
sudo mv IOAHCIBlockStorage IOAHCIBlockStorage.orig
sudo cp IOAHCIBlockStorage.orig IOAHCIBlockStorage
sudo /usr/bin/perl -pi -e 's|\x8b\x4a\x00\x00\xeb\x03|\x8b\x4a\x00\x00\xe8\x01|g' IOAHCIBlockStorage
sudo /usr/bin/perl -pi -e 's|\x74\x0e\x48\x8d\x3d\x72\x92\x00\x00|\xbf\xc8\x00\x00\x00\x90\x90\x90\x90|g' IOAHCIBlockStorage
sudo touch /System/Library/Extensions

Update: Updated fix for “Still waiting for root device” on OS X 10.8.3 Mountain Lion

This fix has been made possible due to countless hours spent by bcc9 from InsanelyMac forums reverse-engineering Apple’s work and his original script.