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I cannot install new plug in to my linux computer. It keeps asking authentication required that needs a password. I do not know what the password is. Pls help me identify the problem or remove the restrictions so that I could install any application freely and easily.

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marked as duplicate by Seth, Rinzwind, Eric Carvalho, Kevin Bowen, Basharat Sialvi Apr 14 '13 at 0:48

This question was marked as an exact duplicate of an existing question.

Can you be more precise with your question? Are you asking how to recover the root password of your linux computer that you have physical access to? – DrSAR Apr 12 '13 at 0:37
Hello DsSAR, I do not have any access to the password. I just bought a new PC of Linux OS. It surprised me I cannot play a video or an mp3 because they require a plug-in to be installed. When I installed the plug-ins, a dialog box appears and it requires me to input an authentication password. I do not know what is the password. Can you help me find the root or the settings for that authentication program, so I can change the setting into no authentication required? – Blessie Apr 12 '13 at 1:24
@Mods, incorrectly flagged. Please ignore! – user25656 Apr 12 '13 at 2:39
There is no such thing as "change the setting into no authentication required". If that was possible, there would be no point of having any authentication for anything (it would defeat all security measures). You need to either get the password from the people you bought the computer from, or reinstall the OS from scratch and choose a new password (and remember it!). – Robru Apr 12 '13 at 2:46
I think this question fits into services provided by Ubuntu, if the OP is using Ubuntu. – green Apr 13 '13 at 11:37

I feel awkward coaching you through cracking a password but here is a first attempt:

I presume you must be somehow logging into the system as some user. (When you bought the computer, did they create an account for you? Or did you just start to use an account that they had previously used - that feels wrong, a bit like a second-hand toothbrush)

Assuming you have your own account or you are using one they gave you, there is a chance that it is privileged to execute commands as super-user (sudo command). I suggest you give that a try:

$ whoami
$ sudo passwd   # this will change the root passwd
[sudo] password for DrSAR:       # enter your user password
Enter new UNIX password:         # this is the new root password
Retype new UNIX password:        # try to get it right a second time
passwd: password updated successfully

If you do not have super user privileges, there are other ways to at least overwrite the root password. However, if you acquired the computer rightfully, they should give you the root password.

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thanks for the info DrSAR. though I do not know all the codes you gave me. But i will try to resolve the issue. thanks for giving the idea that maybe i purchased a used unit. so, i could act immediately in the situation. It's my first time to use linux. so i really have to start from scratch. Have a good one! – Blessie Apr 12 '13 at 5:01

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