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registration re%uired'

How do I reset a lost administrative

password?

up vote ..down vote&avorite 53

()m working on a Ubuntu system using a /anasonic C012+ 3aptop' My Clienthas completely &orgotten his Administrative /assword' He doesn)t evenremember entering one4 however it is there'

()ve tried the suggestions on the 5ebSite and ( have been unsuccess&ul in

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deleting the password so that ( can download applets re%uired &or running some&iles' Do you have a solution6 ( look &orward to hearing your response'

 password 

shareimprove this %uestion

edited Sep *7 )*8 at 9:8; 

Sergey*<'9k8;;<

asked =an 9+ )** at *;:2+user77+;

reboot the machine in single user mode' debuntu'org>recover1root1password1single1user1mode1and1grub ?  aspit@er  =an 9+ )** at *;:27

#ry &ollowing these instructions: psychocats'net>ubuntu>resetpassword  ? csgeek  May *8 )*8 at 8:;

13 Answers

active oldest votes 

upvote*+.down

vote

By de&ault the &irst user)s account is an administrative account- so i& the U( is promptingyou &or a password it)s probably that person)s user password' (& the user doesn)tremember their password you need to reset it' #o do this you need to boot into recoverymode'

Boot up the machine- and after  the B(S screen- hold down the le&t Shift key' ou willthen be prompted by a menu that looks something like this:

()ve noticed on some systems that timing when to hit the le&t Shift key can be tricky-

sometimes ( miss it and need to try it again'

Hit the down arrow until you select the 8nd entry &rom the top Ethe one with the

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recovery mode in the descriptionF and then hit Enter'

 Gow you should see this menu:

Using the arrow keys scroll down to either root or netroot Edoesn)t matter in this caseFand then hit Enter'

ou should now see a root prompt- something like this:

root@ubuntu:~#

At this stage it is possible you have a read1only &ilesystem' ou have to remount it withwrite permissions:

mount -rw -o remount /

 Gow we can set the user)s password with the passwd command' E(n this eample ( will

use orge as the eample- you need to substitute whatever the user)s username isF:

passwd jorgeEnter new UNIX password:et!pe new UNIX password:passwd: password updated su""essfu!root@ubuntu:~#

#ype in what you want the new password to be at the prompt' A&ter it)s success&ul

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reboot the machine and the user will be able to log in with their new password'

• Iecovery Mode documentation

• 3ost password documentation

shareimprove this answer edited Aug 8+ )*8 at *<:++ 

answered =an 9+ )** at *<:+9

=orge Castro89'8k2+88*;;2

( ust tried it and passwd username worked' ()m very surprised' 5hy is this not

considered a security issue6 Eespecially &or desktop /CsF ?  Mohamed Meligy Sep89 )*8 at 2:;8

*9(t isn)t a security issue- because you still have to be sitting in &ront o& the machineto do this' And i& you have physical access to the computer you can do prettymuch anything to it anyway' ?  Bobble ct 9 )*8 at +:2*

9

=ust to &ollow1up on Bobble)s correct comment: i& you have physical access to amachine- you can take the disk out and mount it on a totally separate systemwhere you do have root' =ust as one eample' #he only protection against &ull datacompromise in the &ace o& physical access is strong disk encryption' ?  ariel&  Mar 9at *7:27

( had to go the route o& editing the boot command' But your note here about

remounting was the bit ( was missing' Here is how to edit the boot command:makeuseo&'com>tag>how1to1reset1any1linu1password   ? Chrono0ish May *< at*:88

upvote*.downvote

es you can change the old password via Jrub

*' (& you have a single1boot EUbuntu is the only operating system on yourcomputerF- to get the boot menu to show- you have to hold down the Shi&t keyduring bootup

8' (& you have a dual1boot EUbuntu is installed net to 5indows- another 3inuoperating system- or Mac S K4 and you choose at boot time which operatingsystem to boot intoF- the boot menu should appear without the need to holddown the shi&t key

9' 0rom the boot menu- select recovery mode- which is usually the second bootoption'

;' A&ter you select recovery mode and wait &or all the boot1up processes to &inish-you)ll be presented with a &ew options' (n this case- you want the Drop to root

 shell prompt  option so press the Down arrow to get to that option- and then

 press nter to select it

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2' nce you)re at the root shell prompt- i& you have &orgotten your username aswell- type s /home Esmall letters L not capitalsF' #his will list all the user

accounts in your set up'

' #o reset the password- type passwd username where username is the usernameyou want to reset eg' passwd m!sterio in my case

<' ou)ll then be prompted &or a new password' 5hen you type the password youwill get no visual response acknowledging your typing' our password is still

 being accepted' =ust type the password and hit nter when you)re done' ou)ll be prompted to retype the password' Do so and hit nter again'

.' Gow the password should be reset' #ype e$it to return to the recovery menu'

7' A&ter you get back to the recovery menu- select resume normal boot - and useUbuntu as you normally wouldonly this time- you actually know the

 password!

Hope this helps' Sorry ( couldn)t add images as ()m on my phone

shareimprove this answer 

edited Apr * )*8 at ;:*< 

Alaa<;9*9

answered Mar 9* )*8 at 8*:;7

Mysterio8-279;99<;

#his o&&ers a route &or when you &orget both userid and  password- which would alsowork with N=orge Castro)s answer' ?  Bobble ct 9 )*8 at +:27

upvote**downvote

(& =orge)s method didn)t work &or you- as it didn)t &or me- here is another method' ( hadto try something di&&erent because:

*' My USB keyboard did not work at the root prompt⋯ probably hardwareeither keyboard or mainboard' #he &i ( used was &ind an old /S>8 keyboardEthe little round plugF and use that'

8' 5hen ( used passwd username to change my password- it &ailed because o& a

 bad token or such' #his called &or drastic measures'

The Drastic Measures

This is a very dangerous thing to do! =orge)s method should be used4 only do this incase that method doesn)t work'

Do this at your own ris ' (t did work &or me on my **'*+ system'

#he idea is to set the user)s password to blank Eor nullF 1 this allows you to ust press

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Enter at the %assword: prompt'

Still at the root prompt &rom =orge)s method- &irst remount the root &ile system as read1write by using this command:

mount -o remount&rw /

•  Gow you are a super1user on this system' Tread lightly.

#hen edit the password shadow &ile to remove the encrypted password &or yourusername' #ype inO

nano -' /et"/shadow

#he nano editor will display the contents o& the &ile' ach line will have the &orm

name:⋯:⋯:⋯( where⋯ is a string or null EemptyF' ne o& the lines will start withyour username' #he &irst⋯ a&ter your username is your encrypted password' As an

eample:

username:)*)am+eN"jp)%prj,E.0Ut1w2fE3456:*7896:6:88888::::

where )*)am+eN"jp)%prj,E.0Ut1w2fE3456  is the encrypted password'

Care&ully delete the encrypted password leaving the all the P:Ps- so it looks like this:

username::*7896:6:88888::::

#hen type trl"#- hit the enter key to save- then trl"$ to close nano'

Ieboot and you will have an empty Eor nullF password' Be sure to use passwd

username in a terminal to set or reset your user password'

Source &or /S>8 workaround was here'

Sources &or the drastic measures were here and here'

 Gote on nano Q the -' option makes a backup o& the original edited &ile- same namewith aPRP appended'

share improve this answer 

edited Mar 9+ )*8 at +:;+ 

David<28;8*

answered Dec 8 )** at 8+:22

keepitsimpleengineer *-9.*+9*

8ou can also use this method by booting with a di&&erent disk and editing

>etc>shadow a&ter mounting the appropriate disk' ?  David Mar 87 )*8 at 89:28

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upvote*+down

vote

Ubuntu does not come with an ;dministrati<e password' #here is only one initial

account- the user account- which can be used to eecute administrative tasks' 0oreample- to get a root shell you run

) sudo -i=sudo> password for m!usera""ount: # here !ou t!pe the user?spassword#

A lot o& people that have Uni background or eperience with other distributionsstumble on this issue %uite o&ten'

#he command

su

will always &ail because the root account is locked4 it cannot be accessed directly or

you cannot login directly to root'

#here are great advantages in using the sudo &acility'

shareimprove this answer 

edited *< hours ago 

guntbert8-;;28<8

answered =an 9+ )** at *2:2.

user;*8;;-+;<<8*

( pre&er sudo -s to sudo su -' & course- i& you need Proot login shellP- then do

sudo su - root by all means' ? Mikko Iantalainen Dec *8 )*8 at *+:+2

NMikkoIantalainen- ( ust changed the sudo command above- your comment might be obsolete now :1F ? guntbert *< hours ago

up vote< downvote

( was able to use =orge)s method 1 the one above with the nice screen shots 1 with a&ew minor changes' ()m using Ubuntu **'*+

0irst- when booting up 1 don)t press the le&t shi&t key until the B(S screen goes black and then immediately press and hold the le&t shi&t key'

#hen- a&ter perhaps a minute and a number o& lines o& tet scroll on the screen- ( gotthe &irst menu- but with a couple o& &ewer lines 1 ( chose the second line'

#hen ( got the Iecovery Menu 1 but when ( chose Drop to Ioot Shell /romptEbottom itemF ( was root but couldn)t reset the password 1 because the disks wereIead nly' #ype eit and get back to the Iecovery Menu

#here was a choice Enot shown on =orge)s screen shotF to Iemount Iead>5rite Used

the down arrow to go to it- then le&t arrow to get to and nter 1 and it mounted the

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disk I5'

#hen again to Drop to Ioot Shell /rompt and ()m root and can write 1 so passwdusername had me enter the desired password twice 1 then eit to go back to

Iecovery Menu Iesume normal boot and everything worked &ine with my new password! ()m the only account on this bo- and my password works with sudo so (apparently have Administrative /rivileges'

#his was less eciting than editing >etc>shadow but ( was glad to trade theecitement &or a nice ending'

share improve this answer 

answered =an * )*8 at 9:*;

Henry Scha&&er <***

up vote2 downvote

(& you &orgot you password &or your Ubuntu system you can recover using the&ollowing steps:

*' #urn your computer on'

8' /ress ES, at the grub prompt'

9' /ress e &or edit'

;' Highlight the line that begins erne - press e

2' Jo to the very end o& the line and add rw initA/bin/bash

' press enter- then press b to boot your system' Your system will boot up to a

 passwordless root shell.1

<' Gow issue the command passwd username *where "username" is the user for which you want to change the password.

.' #hen you will be asked to give new password:

Enter new UNIX password:

1Source:ubuntugeek 

ther Iesources:

Ubuntu Documentations

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Ubuntu Help

/sychocats

shareimprove this answer 

edited Apr 8 at 7:2 

Iadu Maris898*9

answered =ul *. )*8 at *7:22

Mitch*2'k822*

#he / may not know what to do at the shell' ? bsessiveSSℲ =ul *. )*8 at 8+:*+

upvote ;

downvote

0irst- you have to reboot into recovery mode'

(& you have a single1boot EUbuntu is the only operating system on your computerF- toget the boot menu to show- you have to hold down the Shi&t key during bootup'

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0rom the boot menu- select recovery mode- which is usually the second boot option'

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A&ter you select recovery mode and wait &or all the boot1up processes to &inish- you)ll be presented with a &ew options' (n this case- you want the Drop to root shell promptoption so press the Down arrow to get to that option- and then press nter to select it'

#he root account is the ultimate administrator and can do anything to the Ubuntuinstallation Eincluding erase itF- so please be care&ul with what commands you enter inthe root terminal'

nce you)re at the root shell prompt- i& you have &orgotten your username as well- type

s /home

#hat)s a lowercase 3- by the way- not a capital i- in ls' ou should then see a list o& theusers on your Ubuntu installation' (n this case- ()m going to reset Susan Brownmiller)s

 password'

#o reset the password- type

passwd username

where username is the username you want to reset' (n this case- ( want to reset Susan)s

 password- so ( type

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passwd susan

ou)ll then be prompted &or a new password' 5hen you type the password you will getno visual response acknowledging your typing' our password is still being accepted'=ust type the password and hit nter when you)re done' ou)ll be prompted to retype

the password' Do so and hit nter again'

 Gow the password should be reset'

#ype e$it

to return to the recovery menu'

A&ter you get back to the recovery menu- select resume normal boot- and use Ubuntuas you normally wouldonly this time- you actually know the password!

source

shareimprove this answer 

answered Apr * )*8 at 8:2*

Iingtail7-997<89*8<

upvote 9downvote

ou can change your password i& you have access to the &ile /et"/shadow Emaybe with

your root account- via sudo &rom anotother account- &rom recovery mode- or with a3iveCD>DDF'

#his shadow password &ile has all the users and encrypted passwords Eas well as otheradministrative in&ormationF &or the system' #he &ields are separated by : ' 0or eample :

54UBUSEN;3E:)C),u*i.o)D0n;8Fj'eGm3H6d'd*IJu17*ds%0UdH7X89gK%wwmD6<dIEI5FED$E"5;,o3bo5ho<rp!JLm1tD':*GG96:6:88888::::

#he password is the second group o& characters a&ter 54UBUSEN;3E- between the twocolons' ou can replace this with a other password- &or eample- you could replace theeisting password string Etruncated &or clarityF:

)C),u*i.o)D0n;8Fj'eGm3H6=>bo5ho<rp!JLm1tD'

with

)C)Fg3d%.n)5"hCrG!sJh8j4g6U%e9Fu1o0LS53ShJbGp1;,rE/;6o!E'+ef4gpbboeoe6L8KJN1uC5F52uD1/

#he encrypted string represents PhackmeP' #his would be your new password'

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shareimprove this answer 

edited Gov 9 )*8 at 88:9+ 

 belac%ua<-8*99

answered =ul *. )*8 at *7:2<

AndrTs Iicardo #orres Martne@928*;

up

vote8downvote

 Go- there is Pno wayP to retrieve the old password'

es- you can change the password without knowing the old one' #he process isdescribed on several sites on the net- easily &ound via a search Ehttp:>>www'google'com>search6clientVubuntuLchannelV&sL%VchangeW&rogottenWpasswordWubuntuLieVut&1.LoeVut&1. F

(& you do that however and happened to have used an encrypted >home1directory &or thatusername you are likely not to gain access to the &iles in your >home1directory Eand i&you do then Ubuntu should be uninstalled'''F

shareimprove this answer 

answered Mar 9* )*8 at 8*:;*

user287+;

87*

upvote8downvote

(n which S have you &orgot the password- Ubuntu or K/6 0or Ubuntu- in the bootJIUB menu- you may append initA/bin/bash to the kernel boot parameter to get a

root shell'

shareimprove this answer 

answered May *8 )*8 at 8:;;

KiX =YlTi*-2272**8

(t is the password o& Ubuntu my &riend 'And ( got it done 'Any way a big thanks toyou too &or your kindness Kie' ?   Goah Dia@ May *8 )*8 at 9:8*

n the askubuntu site you ask &or 5indows Kp6 :D ?  sai.7 Sep *7 )*8 at ;:**

up vote* downvote

#hese answers seem to re1open the debate on Security versus Convenience'

3ibre &&ice advises that i& you &orget a password to a &ile- it cannot be retrieved-

and ( believe MZ cel and 5ord operate similarly'

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(& ( boot my computer in 5indows PSa&eP mode Ee%uivalent o& PIecoveryPF- ( donot need a password or even administrative privileges to log in as Super1administrator- which parallels the 3inu situation described above' However- ( could

 put one in- which in the event o& my computer being lost or stolen would mean that

5indows is more secure than 3inu'

( am not suggesting that 3inu should- or even could change this as the system iscertainly more secure against the much greater threat o& hacking- but does it notmean we must always be aware that we are not as private as we would like to be6

shareimprove this answer 

answered Gov *7 )*8 at .:8+

5JCman.<<

5e can put a password to the 3inu Ubuntu root too! ncrypted &ilesystem is theonly security- whether 3inu or 5indows' /rivacy isn)t an issue here' /rivacycomes into play when you are online' ? Sri May *2 at 2:*.

up vote* downvote

0rom the o&&icial Ubuntu 3ost/assword documentation:

*' Ieboot your computer 

8' Hold shi%t during boot to start JIUB menu

9' Highlight your image and press )e) to edit

;' 0ind the line starting with PlinuP and append rw initA/bin/bash at the

end o& that line

2' /ress ctrl1 to boot'

' #ype in passwd username

<' Set your password'

.' #ype in reboot' (& that doesn)t work- hit "trWatWde

#his works &or 3inu Mint *;- too'

&ey'oard"(ayout

"5I#

shareimprove this answer  answered Mar ** at *:92

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moose;;;*;*<

up vote1* downvote

Somehow booting into recovery mode did not work &or me because it would not boot into the root system' And when ( tried to change the root password it asked me&or the root password- which ( didn)t have' An alternative to this problem is usingUKterm which is a simpler version o& terminal and seems to have root systemcapabilities' =ust type in PpasswdP and enter your new password and it)s changed'

#his works &ine &or Ubuntu *'*+' to bring up command line' nter sudo passwd root'nter new password 8K' back to JU(' 3ogout- then login as root to test'

share improve this answer 

edited =un *< )*8 at *.:*7 

Community[*

answered Mar 87 )*8 at 89:82

\oo;

#his un&ortunately won)t work &or most cases' ? belac%ua  Gov 9 )*8 at 88:98

protected 'y ommunity) Apr 1* +1, at *-./

#his %uestion is protected to prevent Pthanks!P- Pme too!P- or spam answers by new users' #oanswer it- you must have earned at least *+ reputation on this site'

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