Install OS X Snow Leopard from a USB flash drive
By Dan Hinckley
The steps below will guide you through how to Install OS X Snow Leopard from a USB Flash Drive. Alternatively, you can also read these instructions on how to install OS X Lion from a USB Flash Drive.
Apple officially released Snow Leopard a couple years ago and consumers can still find the latest version of OS X at Apple Stores and resellers across the country.
At version 10.6, Snow Leopard, focused more on improving speed and performance than adding new features to OS X. With the operating system available to customers, individuals are ready for their upgrades.
Installing OS X From a USB Drive
Like other versions of OS X, Snow Leopard can be installed from a USB drive. This is especially beneficial to Macbook Air users looking to install the OS without a DVD drive. To do this, you’ll need to prepare your USB drive with the installation files. Like many of our other Mac Help articles, the steps listed below worked particularly for Snow Leopard but should also work for installing OS X from USB on Leopard.
The installation files sit at 6.2gb on the Snow Leopard DVD, so you’ll probably need a drive that has at least 8gb available. If you want your installation files to last against the elements, check out this 8 GB Water/Shock Resistant USB flash drive.
After you’ve gotten the correct USB device, connect it to your Mac and prepare it with the Snow Leopard installation files by following these steps:
NOTE:Depending on your flash drive, you may need to follow steps 5 – 7 on installing onto a USB drive to make sure the drive is bootable before you get start. This includes updating the options for the partition so that it is set to a GUID partition. If the USB drive is not bootable you will NOT be able to install from it.
- Open Disk Utility and select the Flash Drive
- Select the Erase tab on the right and then set Format to Mac OS Extended (Journaled). Name the partition you’ll be creating Snow Leopard or OS X Install so you can keep track of your installation device. After you’ve done this, click the Erase button.
- After Disk Utility finishes erasing your old data on the flash drive and setting it as a new partition, it will be ready for the Snow Leopard install files. Select the Restore tab at the top and then drag the Snow Leopard DVD to the Source field. Select your USB device for the Destination file. Click Restore and wait for the restoration to finish (about 20 minutes).
- If the restoration worked correctly you should be able to open your USB device and see the Leopard installation files. If you try and click the Install OS X Snow Leopard icon, you’ll get the message below telling you you can’ install OS X from this volume. IGNORE the message. The next steps will walk you through the installation steps.
- Now that the installation files are successfully on your USB device, be sure to remove the Snow Leopard installation DVD from your drive. Next, restart your Mac and when it first starts to reboot, be sure to hold down the option (alt) key on your keyboard. After a few seconds at least two volumes should appear for you to select from for installation. One of those will be the USB drive we just prepared. Select it.
- After the Snow Leopard installation software boots from your USB drive, follow the on screen instructions for installation. It took about 38 minutes to install Snow Leopard on my machine from the USB drive. I’m curious to see how this compares to the average Mac users, please leave a post in the comments letting us know how long it took on your machine.
- After the installation finishes, it will reboot your computer into your new upgraded version of OS X, version 10.6 Snow Leopard
This method works for installing OS X Snow Leopard onto a Mac from a USB Drive. It should also work for installing Leopard or other older versions of OS X on Intel Based Macs. Check back often for additional help and tips for your Mac.

About Dan Hinckley
Dan Hinckley is an experienced Mac user who converted to Apple products when they introduced them on Intel Processors. He loves helping others get more out of their devices! Subscribe to Maciverse.com to get the latest from Dan and the Maciverse Team!! Find out more about Dan:
Dan's Google Profile
411 Responses so far.
Joe
July 1, 2011 at 4:35 amWorked great – Thanks – Took about 35 mins
Rick DocSouth Southwick
July 2, 2011 at 2:21 pmI'm trying to install 10.6.3 retail family on an iMac with Intel. The hard drive was wipped using the disk utility before I go it. I have followed the instructions to put on a flash drive and cannot see any drive options when holding down the option key. I only see a refresh button and a ==> arrow. I'm using a Lexar 8gb flash drive.
Did the Disk Utility wipe trash the system??
Φίλιππος Λανγερ
July 7, 2011 at 4:57 amFor some reason, when I select the USB by Alt or simply put it as a startup disk, it loads for a while and it shows the grey mask of doom
Any help?
The Amazing Greg
July 21, 2011 at 5:05 pmThanks! Worked great took about 40 minutes.
Edgar Eduardo
August 4, 2011 at 9:22 ammmm not working on a mac book pro i7 quad core.
Scandalous
August 10, 2011 at 6:36 amworks fine w my macbook!!
did it very quickly though, about 20min…
I’m a new Mac user and this was very but very useful..
thanx again
Brettney
August 14, 2011 at 6:24 pmWorked like a charm! Thanks!
Henrique
August 23, 2011 at 9:56 amHi. I have a late 2008 mackbook (white). I´ve been tring to upgrade from leopard to snowleopard, folloing all the intructions on this post. The difference is that I don´t have a retail DVD, so I downloaded about 5 different dmg image disks with mac os 10.6. I didin´t work with any of those. I aways begin the instalation and it fails when it is 39 min to the end. It gives me the messages.
" INSTALL FAILED – Mac OS X could not be installed on your computer. The installer could not copy the necessary support files. Click Restart to restar your computer and try installing again. "
Has anyone seen this message before? Is it a problem with my computer? (I have the Mac OS X 10.5.8 instaled and updated, its got an intel core 2 duo processor and 2 Gb memory.
Haven´t tried the original retail DVD, because I live in Brasil and would have to pay almost 100 dollars only for the DVD and don´t now if it will work. My objective is just meke my macbook able to upgrade to Lion on appstore…
Please heeeeelllllp.
Dan
August 23, 2011 at 10:07 amthe files you download from the internet won't work, you'll need a retail DVD or an image created from a retail DVD.
Messiah Kaeto
August 26, 2011 at 6:50 pmWorks perfectly. Thank you for this guide.
MReyes
August 29, 2011 at 10:53 amAwesome! I don't usually post comments, but your instructions on installing Snow Leopard from a USB Drive were extremely helpful for me. I previously had so much difficulty with a website which directed me to follow 'simple instructions' that caused alot of frustration. Thank you so much for your help.
MReyes
August 29, 2011 at 10:55 amBy the way, it took about 38 minutes to install. Thanks again.
fil
August 31, 2011 at 12:38 amthanks,50min on macbook pro 2006
James
September 1, 2011 at 10:06 pmThank you sooooo much. i've been trying to do this for 3days straight. The Youtube videos i was watching are completely wrong…
chinnie
September 3, 2011 at 7:41 amIt worked! I installed a simple upgrade directly from tiger 10.4, and after a very long, tedious and unsuccesfull install via a DVD. It took me around 40 minutes and I haven't encountered any substantial problems so far.
shahi
September 9, 2011 at 11:18 amThanks it seems to be installing well, installing from a 16GB USB flash drive initially it said it will take 43mins, but seems to be going faster now
JohnDo
September 13, 2011 at 8:52 amThis worked perfectly!! I just followed everything straight through and it took around 40 minutes. I actually downloaded Snow Leopard from a torrent file so I could upgrade to Lion (now I'm in Lion after purchasing it) and bypass the extra $30 I didn't want to have to pay! I think it's not fair that Apple is jacking people by making them pay for Snow Leopard to get to Lion or even with their new thumb drive option (it's a total rip-off). I paid for what I wanted and I'm content.
I basically downloaded the torrent from PirateBay, clicking on the first thing the showed up when I Googled "snow leopard torrent". It's 6GB and it took me like 40 mins to download with about 80GB free space and all other apps closed. I have DSL in a house with 40 other people sharing the network.
I launched the DMG file so the image would mount (appear in the left side of a FInder window) and then that's what I dragged into the Disk Utility Restore source as described in the instructions above. To format my flash drive (I actually used an 8GB SD card with a USB adapter) I erased it and formatted it as Mac OS X Extended (Journaled) and then I went to Partition and clicked on 1 Partition and then Options to create a GUID Partition Table. A blue box appeared that set aside a chunk of data that could not be used so I was down to 7.1 GB capacity but it still worked. My adapter is flimsy too so I was scared but it worked out in the end.
I backed up twice on my 2TB Seagate Free Agent Desk and then shut down and turned it on. The moment I heard the disk spin I held down ALT and eventually my flash drive indicator turned on and the rest was magical. It took about 40 minutes.
I backed up twice more after all the Snow Leopard updates were installed which took about another hour all together. Lion was super fast but I fell asleep installing it.
Steve
November 4, 2011 at 12:33 pmSo, $30 for snow leopard and $30 for Lion = $60 for 2 systems. I think $129 for every new OS was the rip-off, but not $60 total for 2 different operating systems! To each their own, I guess.
I agree that Apple is greedy with some things but this isn't one of them!
Meowert
September 15, 2011 at 3:29 pmRestoring to a flash drive is not needed and doesn't always work.
In my case it caused corruption of the filesystem on the flash drive when the restore was finished.
(it was a Verbatim PinStripe 16GB)
However, a simple Copy of all the files and folders using muCommander worked fine.
Then use Startup Preferences to bless and reboot..
shiori2525
September 23, 2011 at 6:25 pmNice tutorial. Thank you.
promo
September 28, 2011 at 6:07 amJust to follow up on the up-date of this matter on your web site and would want to let you know just how much I appreciated the time you took to generate this beneficial post.
Dirk
October 5, 2011 at 10:32 amGreat! I’ve been looking for this since my dvd drive is broken.
Question: I select the usb, it starts to run when suddenly the icon stops rotating. This has been the problem (can’t get to the desktop). I thought a clean install was the solution, apparently not. What could be the problem?
Thanks for any feedback!
Macbook Pro ’08
astukas
October 6, 2011 at 8:39 ami did everything acording instruction and i had Tiger, the installation took 39 min, and i installed on tiger, not a clean install, everything works so far, i'm proud of myself and thanks a lot to Dan Hinckley fot the instruction, none of my files is missing, so i'm very happy and lucky today!!!
fallychoo
October 8, 2011 at 8:13 amUsed the alt key to boot from USB flash card. Had tried too many times to boot from two retail discs without success. I was about to remove non apple ram to give it my last try before shelving the MBP 2008. Dans method worked very smoothly and quick. No running updated snow leopard. So very grateful. My recommendation would be to erase all data with max erase zeroing for those having trouble.
jake
October 11, 2011 at 10:17 pmI have a Macbook Pro. I did this all, it installed but there are problems updating. If I try to launch software update it doesn’t work, it just freezes. I also can’t use safari or firefox. I even tried to resolve it by trying to install lion, but that didn’t work, as Lion said iI can’t upgrade this OS. What went wrong? I used disk utility. There was some errors while the software was installing, but I don’t know if they are meaningful.
Zahgurym@yahoo.com
October 27, 2011 at 4:41 pmEarly 2008 macbook 4,1. 2.5gb ram.
Took just under 40 minutes.
Thanks. =D
Kardjo
November 2, 2011 at 8:14 am[sorry if repost, i lost connection]
I have Macbook White with:
Model Name:MacBook
Model Identifier:MacBook2,1
Processor Name:Intel Core 2 Duo
Processor Speed:2.16 GHz
Number Of Processors:1
Total Number Of Cores:2
L2 Cache:4 MB
Memory:4 GB
Bus Speed:667 MHz
Boot ROM Version:MB21.00A5.B07
I do all your steps in AData 8 GB usb flashdisk.
While reboot, I hold [Alt] key, and USB appear. Startup oke. I have to choos a language, then…. OOOps !!
I've got this message:
"Mac OS X could not be installed on your computer. Click Restart to restar your computer and try installing again."
FYI…., I put Macbook Pro MC700 core-i5 (Early March 2011) original DVD as source. It was Mac OS 10.6.7.
I make Restore on MC700. Is that the problem?
My currently Macbook White run with Mac 10.6.8. Firmware updated via Software Update.
I just want to make Fresh Reinstall….
Please help me..??
Dan
November 2, 2011 at 8:35 amYou can't use a Macbook Pro DVD with a Macbook DVD. Apple requires you either have a stand alone retail version of the software or the dvd made specifically for your mac.
Kardjo
November 3, 2011 at 8:05 amThank you Dan… I will seek for it.
JB
November 3, 2011 at 10:11 pmyup, i tried to install using the boot with the usb thing… but it never finished. i slept over it and it is still not done… definitely not 40 minutes… i just cancelled it. any help?
Steve N
November 4, 2011 at 12:11 pmCan I partition a 16 GB USB drive (say 10gb, 6gb) or does it have to be 1 partition only?
I’m thinking of putting snow leopard 911 on the 6 GB partition so it will be all on one USB drive as I don’t have any 8 GB flash drives. Thanks !
Claude
November 8, 2011 at 4:36 pmThanks, helped me a lot! My DVD drive didn't work and was sick of Lion.
zak
November 9, 2011 at 11:16 pmif i update this way will it delete all the stuff on my hard drive that is currently on the it?
Nas
December 1, 2011 at 7:06 pmno it will just update your previous system
Brian
November 11, 2011 at 2:16 pmHey there. Did the install from usb flash.
How should I restore/erase my flash drive?
Mac OS (?) ?
Thanks
marlin
November 22, 2011 at 7:40 amWorks GREAT…Thanks!!!
Austin
November 29, 2011 at 7:44 pmSo I was able to follow everything up until selecting the USB drive after I did the restart and holding alt. The USB drive simply did not show up. Any tips? Also, I am not getting the message that I cannot use this volume…
Nas
December 1, 2011 at 9:55 amuse another USB keyboard, some doesn't trigger the boot option
Nas
December 1, 2011 at 9:51 amit works like a charm from a .dmg file I used it on 10 macs, some USB keyboards won't trigger the boot option while holding the Alt key , just use another USB keyboard until you get the right one.
Baggy
December 10, 2011 at 2:21 amWhich .dmg file did you use? Was it a torrent? I'm stuck!
Nas
January 17, 2012 at 10:36 pmit was Mac_OS_X_10.6.0.dmg and i guess i downloaded it from a sharing host i forgot which one , try to google the file name
ZACH
December 4, 2011 at 10:42 amAWESOME TUTORIAL IM IN THE PROCESS OF RESTORING NOW THEN INSTAL HOPEFULLY APPRICIATE IT GUY ILL LET YOU KNOW MY INSTAL TIME!!!
Angel
December 19, 2011 at 10:16 pmcan this be done using .iso instead of .dmg . really new to this and I dont even know whats the difference between them.
Angel
December 19, 2011 at 11:17 pmNever mind my previous question. I did everything the same but used .iso instead of .dmg and its working perfectly. I'm noticing a different right away. so much smoother and the whole process from copying to usb and install took less than an hour.
hanne
December 26, 2011 at 12:54 pmTrying it right now. It's either this or buying a new mac book pro. I run I an old version of Tiger
on a 5+machine.
Hanne
December 26, 2011 at 1:21 pmIt seems to be working fine, thank you,
Hopefully it means I can use this good old machine for another year or so.
great!
wakeldan
January 1, 2012 at 3:08 amI get a Kernel Panic error that says “you need to restart your computer…” in four languages. I can run Mac OS X Lion from my harddrive now flawlessly, so I think it is not related with a hardware malfunction. So what might be the problem?
Gopfter
January 4, 2012 at 9:58 amI get "Mac OS X could not be installed on your computer. The installer could not copy the necessary support files." while in the middle of the install.
- Why is this when so many others are doing great with the same file as I got?
I use 10.5.8 from 2008.
When I check Disk Utility, my HDs name is red and says: The drive has a hardware problem that cant be repaired.
Dan
January 4, 2012 at 10:04 amI think you just answered your own problem. Sounds like your HD is bad and files can't be written to it.
Time for a new HD.
Victoria
January 8, 2012 at 11:22 amIn doing this will I lose all of the files I have on my computer? If so, is there a way to install snow leopard so that my files will be saved? I do not have anything big enough to backup my entire computer, however all that I need to keep is pictures and music.
Russell
January 9, 2012 at 1:22 amThis doesn't seem to be working for me. After reading all of the comments the only reason I can think is that my flash drive is not "GUID" formatted. When I go into Disk Utility it says "disk format: Mac OS Extended (Journaled)". I presume this means it's not "GUID" formatted. Is there any way of making it GUID formatted without starting from the beginning? I live on a pretty remote island in Thailand so technology and help in general is quite hard to come by!
I am running 10.4.11 on a MacBook and I created my boot disk using a legit copy of Snow Leopard. However, the flash drive that I had posted to me from the mainland wasn't quite 8GB, it was 7.6GB, the same size as the file. I got an error when I first copied created the disk image saying it hadn't worked, but when I insert the drive into my MacBook it appears to work fine. Is it possible that one or two files didn't copy over correctly and this is why it's not working?
Aeolas
January 9, 2012 at 1:23 pmthx for this guide
i did it with a Sandisk 32GB CF 60MB/s took from pressing the Install button 28 minutes.
Chris
January 10, 2012 at 7:24 pmHi,
This worked perfectly! One question, however. I purchased my MacBook Pro on Ebay and I was hoping this would do a clean install (wiping all the files and allowing me to create a new admin account). It looks like it just did an update, however and I didn't see an option for a clean install. Should there be one?
Thanks!
Dan
January 10, 2012 at 7:29 pmYes, after booting into the USB drive and before you start the install process, Select Disk Utility from the menu options (I believe it's under Tools). Then format with Mac Journal the Hard Drive. This will clean everything off.
Anonymous
January 22, 2012 at 2:38 amHow do I do this from a PC?
Leave a Reply
Get The Latest From Maciverse
Advertisement
Popular Articles
Apple Topics
Recent Posts
Copyright © 2010 Maciverse.com. All rights reserved.
Site powered by Mangoco