How Do I Reset a Lost Administrative Password? up Vote 88 I'm Working on a Ubuntu System Using a Panasonic CF-50 Laptop
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Ubuntu Community Ask! Developer Design Hardware Shop More › Stack Exchange sign up log in Ask Ubuntu Questions Tags Tour Users Ask Question Tell me more × Ask Ubuntu is a question and answer site for Ubuntu users and developers. It's 100% free, no registration required. How do I reset a lost administrative password? up vote 88 I'm working on a Ubuntu system using a Panasonic CF-50 Laptop. My Client down vote has completely forgotten his Administrative Password. He doesn't even favorite remember entering one; however it is there. 53 I've tried the suggestions on the WebSite and I have been unsuccessful in deleting the password so that I can download applets required for running some files. Do you have a solution? I look forward to hearing your response. password edited Sep 19 '12 at 3:24 asked Jan 30 '11 at 14:50 share improve this question user9904 Sergey 17.3k2447 reboot the machine in single user mode. debuntu.org/recover-root-password- single-user-mode-and-grub – aspitzer Jan 30 '11 at 14:59 Try following these instructions: psychocats.net/ubuntu/resetpassword – csgeek May 12 '12 at 2:46 13 Answers active oldest votes By default the first user's account is an administrative account, so if the UI is prompting you for a password it's probably that person's user password. If the user doesn't remember their password you need to reset it. To do this you need to boot into recovery mode. Boot up the machine, and after the BIOS screen, hold down the left Shift key. You will then be prompted by a menu that looks something like this: up vote 108 dow n vote I've noticed on some systems that timing when to hit the left Shift key can be tricky, sometimes I miss it and need to try it again. Hit the down arrow until you select the 2nd entry from the top (the one with the recovery mode in the description) and then hit Enter. Now you should see this menu: Using the arrow keys scroll down to either root or netroot (doesn't matter in this case) and then hit Enter. You should now see a root prompt, something like this: root@ubuntu:~# At this stage it is possible you have a read-only filesystem. You have to remount it with write permissions: mount -rw -o remount / Now we can set the user's password with the passwd command. (In this example I will use jorge as the example, you need to substitute whatever the user's username is): passwd jorge Enter new UNIX password: Retype new UNIX password: passwd: password updated successfully root@ubuntu:~# Type in what you want the new password to be at the prompt. After it's successful reboot the machine and the user will be able to log in with their new password. Recovery Mode documentation Lost password documentation answered Jan 30 '11 at 17:03 edited Aug 20 '12 at 17:00 share improve this answer Jorge Castro 23.2k50221445 I just tried it and passwd username worked. I'm very surprised. Why is this not considered a security issue? (especially for desktop PCs) – Mohamed Meligy Sep 23 '12 at 5:42 It isn't a security issue, because you still have to be sitting in front of the machine 13 to do this. And if you have physical access to the computer you can do pretty much anything to it anyway. – Bobble Oct 3 '12 at 0:51 Just to follow-up on Bobble's correct comment: if you have physical access to a machine, you can take the disk out and mount it on a totally separate system 3 where you do have root. Just as one example. The only protection against full data compromise in the face of physical access is strong disk encryption. – arielf Mar 3 at 19:59 I had to go the route of editing the boot command. But your note here about remounting was the bit I was missing. Here is how to edit the boot command: makeuseof.com/tag/how-to-reset-any-linux-password – ChronoFish May 17 at 1:22 up vote Yes you can change the old password via Grub 18 down 1. If you have a single-boot (Ubuntu is the only operating system on your vote computer), to get the boot menu to show, you have to hold down the Shift key during bootup 2. If you have a dual-boot (Ubuntu is installed next to Windows, another Linux operating system, or Mac OS X; and you choose at boot time which operating system to boot into), the boot menu should appear without the need to hold down the shift key 3. From the boot menu, select recovery mode, which is usually the second boot option. 4. After you select recovery mode and wait for all the boot-up processes to finish, you'll be presented with a few options. In this case, you want the Drop to root shell prompt option so press the Down arrow to get to that option, and then press Enter to select it 5. Once you're at the root shell prompt, if you have forgotten your username as well, type ls /home (small letters & not capitals). This will list all the user accounts in your set up. 6. To reset the password, type passwd username where username is the username you want to reset eg. passwd mysterio in my case 7. You'll then be prompted for a new password. When you type the password you will get no visual response acknowledging your typing. Your password is still being accepted. Just type the password and hit Enter when you're done. You'll be prompted to retype the password. Do so and hit Enter again. 8. Now the password should be reset. Type exit to return to the recovery menu. 9. After you get back to the recovery menu, select resume normal boot, and use Ubuntu as you normally would—only this time, you actually know the password! Hope this helps. Sorry I couldn't add images as I'm on my phone edited Apr 1 '12 at 4:17 answered Mar 31 '12 at 21:49 share improve this answer Alaa Mysterio 764313 2,59343374 This offers a route for when you forget both userid and password, which would also work with @Jorge Castro's answer. – Bobble Oct 3 '12 at 0:59 If Jorge's method didn't work for you, as it didn't for me, here is another method. I had to try something different because: 1. My USB keyboard did not work at the root prompt ⋯ probably hardware either keyboard or mainboard. The fix I used was find an old PS/2 keyboard (the little round plug) and use that. up vote 2. When I used passwd username to change my password, it failed because of a 11 bad token or such. This called for drastic measures. down vote The Drastic Measures This is a very dangerous thing to do! Jorge's method should be used; only do this in case that method doesn't work. Do this at your own risk. It did work for me on my 11.10 system. The idea is to set the user's password to blank (or null) - this allows you to just press Enter at the Password: prompt. Still at the root prompt from Jorge's method, first remount the root file system as read- write by using this command: mount -o remount,rw / Now you are a super-user on this system. Tread lightly. Then edit the password shadow file to remove the encrypted password for your username. Type in… nano -B /etc/shadow The nano editor will display the contents of the file. Each line will have the form name:⋯:⋯:⋯… where ⋯ is a string or null (empty). One of the lines will start with your username. The first ⋯ after your username is your encrypted password. As an example: username:$1$amFeNcjp$PprjCKEVk3UtzKwWfEMOY0:14920:0:99999:7::: where $1$amFeNcjp$PprjCKEVk3UtzKwWfEMOY0 is the encrypted password. Carefully delete the encrypted password leaving the all the ":"s, so it looks like this: username::14920:0:99999:7::: Then type Ctrl-O, hit the enter key to save, then Ctrl-X to close nano. Reboot and you will have an empty (or null) password. Be sure to use passwd username in a terminal to set or reset your user password. Source for PS/2 workaround was here. Sources for the drastic measures were here and here. Note on nano ― the -B option makes a backup of the original edited file, same name with a"~" appended. edited Mar 30 '12 at 0:40 answered Dec 2 '11 at 20:55 share improve this answer David keepitsimpleengineer 752421 1,6381031 You can also use this method by booting with a different disk and editing 2 /etc/shadow after mounting the appropriate disk. – David Mar 29 '12 at 23:52 Ubuntu does not come with an Administrative password. There is only one initial account, the user account, which can be used to execute administrative tasks. For example, to get a root shell you run $ sudo -i [sudo] password for myuseraccount: # here you type the user's password # A lot of people that have Unix background or experience with other distributions stumble on this issue quite often. up vote The command 10 down su vote will always fail because the root account is locked; it cannot be accessed directly or you cannot login directly to root.