The long-awaited RedSn0w untethered jailbreak for iOS 4.2.1 was released earlier today by the iPhone Dev Team. As we mentioned before, it is still a beta version, which means it is very unstable and causes a few noteworthy bugs.

We’re aware that some of you are true dare devils so we thought it’d still be a good idea to post a guide on how to untether your iPhone. This step by step tutorial will show you how to untether your iPhone 4.2.1 using RedSn0w. This only works for the iPhone 4, iPad, and iPod Touch 4G…

Note: You will need a Mac to use this tutorial, this currently does not work on Windows machines.

Step 1: You will need to be already on iOS 4.2.1, so if you have not done so, update your iPhone firmware to iOS 4.2.1 via iTunes update. Next, jailbreak your iPhone running iOS 4.2.1 with Redsn0w using this tutorial. You may want to use Redsn0w beta 0.9.6b6 which addresses a battery drain issue.

Step 2: Download RedSn0w 0.9.7b1 from our downloads section and make sure your iPhone is connected to your Mac.

Step 3: Download usbmuxd, open a terminal window on your Mac, and navigate to the python-client directory inside the extracted usbmuxd folder.

Step 4: In your terminal window type the following commands:

chmod +x

./ -t 22:2222

You should now see a dialogue that says “Forwarding local port 2222 to remote port 22” (see screenshot above). This is a very important step, if you run Redsn0w without this running, you will have to restore to stock firmware, and try again.

Step 5: Execute RedSn0w 0.9.7b1, and browse for your iPhone 4.2.1 firmware. It should be in the “~/Library/iTunes/iPhone Software Updates” section on your mac. If you don’t have it on your Mac, you can download it from our downloads section. Once the IPSW file has been identified successfully, click next.

Step 6: You will see a small box pop up saying “preparing jailbreak data”. Once that completes, you will be at a screen that features multiple checkboxes. Cydia will be checked by default.

Step 7: Next, check the box that says “Jailbreak Monte (untether)”. Upon doing so, a new box will pop up asking for the 4.2b3 IPSW (Google is your friend). Once you’ve located the beta firmware, click next.

Step 8: At this point, you will see a screen asking you to prepare to put your iPhone into DFU mode. Make sure that your iPhone is plugged into your Mac and powered OFF. Click Next.

Step 9: Follow the on screen instructions to put your iPhone into DFU mode.

Step 10: It’s smooth sailing from here, grab a soda, sit back, and watch.

For those of you who are old hats at jailbreaking, you’ll witness some familiar activity on your iPhone.

Step 11: The Redsn0w dialogue should indicate that the process is done; Click ‘Finish’ to close Redsn0w. Enjoy your untethered, jailbroken iPhone 4 running iOS 4.2.1!

Again, remember that there are some known issues with the Redsn0w beta, so make sure you take ample note of those.

What do you think, are you a true dare devil, or do you still planning on waiting it out for an official release?

  • MALdito

    Nah, its better to be patient for the stable version then to jump the gun and take this risk.

    • Naomi

      Hey I was thinking of jailbreaking my iphone and was going to try this one after I saw your message. What do you mean by stable version? Is it safer? and what is the name of the stable version?

  • Eric2

    Nope. Will wait.

  • icyhotonmynuts

    Wow, what a complicated process.
    Thanks Geohot for a uncomplicated 1-ish click solution on the 4.1 JB.


    but i don’t have shsh save in my cydia.what should i do?please help me

    • Duck

      If you have updated to 4.2.1 then you can jailbreak using this method (unstable), or perform a tethered normal 4.2.1 jailbreak (google it). I’m asuning you didn’t save shsh for 4.1, that only means you can’t downgrade to firmware you don’t have it saved for. I’m going to wait for an untethered 4.2.1 method which doesn’t require the beta. I hope this helps you out

  • Chico

    I’ll also wait for the stable version

  • garry

    can i download on my phone with my window pc?

  • The Master

    i just jailbroke mine.. very unstable… just wait for a better jailbreak…. youtube doesn’t even work with this jailbreak and also multitask doesn’t work either…

  • Gaurav

    When to expect unteethered Unlock & JB for Iphone 4.1 8b117 2.10.14 in India?

  • alex

    stuck on installing bundles

  • coupeborgward

    Any ETA for 4.2.1 untethered jailbreak that support 3GS (new bootrom) ?

  • Zeb Sogo

    Yeah Sod all that especialy the terminal stuff I’ll wait

  • Hey, i just jailbroke my 4.2 iPad using your guide, it was time consuming but relative easy. it would not have been time consuming had I not accidentally deleted my original copy of iPad 4.2b3 IPSW

  • K-town

    I have cydia on my iPhone 4, it did exactly like the video shows, but why is cydia (white) and will not open? I prolly screwed up. Can someone help me? iPhone 4 , 4.2.1, and the 3.10.1( modem firmware) thx alot, really!!

    • wax4554

      Thats because it’s tethered, Just boot tethered from the redsn0w and you will be fine, also u must know that each time u restart ur phone it wont work, u must reboot from the redsn0w

    • adam

      did the same for me but i relized i downloaded the wrong restore then i downloaded the right one and it worked hope this helped

  • blargh

    How come I can do all this.. But I can’t find the final (untether Monte) ipsw? How do I do this final step?

    • bokito

      did you find out how to find the ipsw thing same prob..

  • Zaitona

    I have this version of iTunes but on a 3G iPhone, I just updated my phone 🙁 and now I want to jailbreak it, can I still use this?

  • 3lm0

    im in windows…anyway i can daredevil this and take it to windows? i’m currently tethred if i cannot tell me any updates about 4.2.1 jb on ipod touch 4g and eta at
    again at rexzed01 @

  • bokito

    i tried it but i always get invalid 4.2b3 IPSW what does that mean?

  • dell630

    I have an iphone 3G, stupidly did not do my research before I updated to 4.1.2, now my phone will load contacts, messages, and apps, but the actual phone won’t work. If someone calls me I can answer, but I can’t call anyone without having to go into my contact list. Also, every time I try to adjust the volume listening to my ipod, phone freezes and I need to reboot. Did I just screw myself but updating? I downloaded redsn0w 9.6.b4, also downloaded the proper firmware, tried to reboot “just boot tethered right now” thru redsn0w, and it’s still not working properly, any help is appreciated!


  • james kyle

    is this a possible thing to do on my windows vista machine? or is it only able to be done on a mac?

  • Andrew Jenson

    this will not work at all i keep on doing it but ive had no luck at all it always pops up but crashes and it makes my safari crash any help?

  • jibz

    your all just better of waiting for limerain or spirt 4.2.1 i jail broke my iphone 4 yesterday tethered which btw is very annoying every time you reboot ur device you need to be using the redsn0w software on ur computer which is alot of the time when downloading from cydia as some things require a reboot.
    it also just keep crashing when i try calling out or talking on the phone and in the end i had to do a full system restore it might work well for some of u but i recommend to just wait a bit longer i am not sure exactly when the new 4.2.1 software is released on other programs but i would recommend limerain to people its the best out so far.

  • Jafy

    Did the 4.2.1 jailbreak tethered, works fine on my iphone 4. I even used win 7 without xp mode. Everything works inc bluetooth.Tethering is lame, so i tried a system restore, but I can’t do it! Im getting errors… Any recommendations?

    • Joax

      Delete what you wrote in the host file in windows, and try again 🙂

    • Joax

      Delete what you wrote in the host file in windows, and try again

    • Joax

      Delete what you wrote in the host file

  • I’ve jailbroken my iPhone 4 using RedSn0w 0.9.7 beta 6, and it’s been working without a hitch so far.

  • this is old news and should be removed

  • mike

    Please, I need the windows version. What’s the release date of the untethered jailbreak for windows iOs 4.2?

  • Anonymous

    Looks like 4.3 will be release before an official 4.2.1 untethered Jailbreak is released. What the hell is the damn holdup? MuscleNerd announcing an untethered Jailbreak by Christmas was a total joke. Jan. is almost over and still no sign of an untethered JB.

  • Anonymous

    does anyone know where i can find a working link for RedSn0w 0.9.7 beta 1?

  • Duck

    I’m going to stick with a tethered 4.2.1, the music player works and I can still watch movies if I don’t boot properly. I’ll go untethered when I can do it properly, without those 4.1 blobs I didn’t save, and without downloading another ipsw. But I’m still happy with the jailbreak I got.

  • Duck

    I’m going to stick with a tethered 4.2.1, the music player works and I can still watch movies if I don’t boot properly. I’ll go untethered when I can do it properly, without those 4.1 blobs I didn’t save, and without downloading another ipsw.

    • Jon

      Hey so if u don’t reboot tethered after turning off phone what doesn’t work when it’s back on? Can I still make calls? I know Cydia and safari won’t woke,,let me know thanks

      • Duck

        Any application that doesn’t have code signed by Apple will fail to launch if you dont boot tethered correctly. Also a according to the website “and any applications that have to be moved by Cydia will fail (Safari being the most notable)” I hope this helps you out

  • Daniel

    Hey guys do you have any idea when the untethered is going to be released because i cant get greenpoison to work. and doesnt have a jailbreak for 4.2.1.

  • ShanePersonPeople

    I tried, but i couldn’t get the Jailbreak Monte Option.

  • Abdo

    Does anyone know wen the official release of the untethered jb for ios 4.2.1 for windows will be??
    All this waiting is getting boring -.-

  • JailbreakingSinceJan2010

    WHAT THE HECK? i used to have a 4.2.1 teethered jailbreak. after doing this my iphone crashed and wont start up. itunes said it wont work unless i reset to factory settings. this made me pissed. all my fucking apps and music GONE!

    • Duck

      Well, this was a beta and you should of known the risks involved, sorry for your loss though. Wait til a 4.2.1 jailbreak is out of beta.

  • Duck

    Wait no longer, greenpois0n now has an untethered 4.2.1 jailbreak for all iDevices

  • Zeeshan

    there is no unlock for iphone 4 ios 4.21 ??????

  • Faisal

    how i can download this Jil Porogram?

    i was trying so many time but i dont know how?

    can you please help?

  • Rick

    how i break code to not pay att so i can tether with my phone???

    I am sick of being nicle and dime by them