asking for password to open ubuntu in inital boot

while initially booting window asking for password,after typing password it shows authentication failed

to know my forgotten boot password

Are you asked for the password before Ubuntu even loads?

I don't remember user and password what i can do

You can do this: http://www.psychocats.net/ubuntu/resetpassword

or

To discover your user and restore (change) the password you can:

Start the pc the when you see the GRUB row...

Press ESC.

Press "e" for edit.

Highlight the line that begins kernel ………, and press "e"

Go to the very end of the line, add rw init=/bin/bash

press enter, then press "b" to boot your system.

Your system will boot up to a passwordless root shell.

Type in grep -i 1000 /etc/passwd

The system must show a row with your user name at the start of the row
for example:
danilo:x:1000:1000:ubuntu,,,:/home/danilo:/bin/bash

Here my user is danilo

Then to change your user password type in:

passwd username

or

passwd -d username

change username with your real user

Set your password.

Type in:

reboot

or

reboot -f

Hope this helps

I am a TOTAL NEWBIE when it comes to Linux. Before installing Linux on a new Netbook I am trying it out on my Desktop running WinXP SP3 with 3.2Ghz CPU and 4GB RAM and tons of HDDs. I do not want to install on my desktop but to test by booting from the USB memory stick ‘drive’.
I have successfully created a bootable USB drive from the file 'ubuntu-9.10-netbook-remix-i386.iso' using 'unetbootin-windows-429.exe'.
I have modified my Boot Sequence to boot from USB first and all seems OK. The sequence of events is as follows.

1. I get a UNetbootin dialog with the following options:
 Default
 Help
 OEM…..etc

2. If I accept ‘Default’ the computer boots from the USB and I get the Ubuntu screen with a ‘Log In’ dialog showing Username – I leave it blank and hit Log In to bring up the next dialog showing Password. I have not set either a username or a password and what is more I do not use them when I open my current OS [Windows XP].

3. At this stage I now get a lower ‘Task Bar’ showing – Language [US English], Keyboard [US], Sessions [GNOME]. The last one also offers ‘Failsafe GNOME’ and ‘xterm’.

4. Again I leave Password blank and hit Log In or Enter and I get the error message:
‘Authentication failed’. I can get no further although, if I hit the ‘little man’ on the lower task bar I can bring up Options for the screen – magnification etc.

5. I then shut down and start again but on this occasion I select ‘HELP’ at the UNetbootin dialog. I then get a ‘DOS type’ screen which rapidly executes a number of steps that are scrolled through on the screen before ending with a (initramfs) prompt.

6. If I again enter ‘HELP’ I get a list of COMMANDS many of which are common to DOS – I have forgotten most of my DOS!.

7. Amongst these commands is ‘uname’ and ‘pwd’ if I type those at the prompt I get ‘Linux’ as uname and ‘/’ as pwd. I have tried using both these as the Log In inputs but still cannot proceed past the Log In phase.
From all of the above I assume that I have successfully created a BOOTABLE USB drive and all that is holding me up is the mystery Username and Password.

I have taken a look at ‘http://www.psychocats.net/ubuntu/resetpassword’ but that does not appear to relate. And what is ‘the GRUB row...’?

All help gratefully accepted.