Forgot password reset or break Windows 7 password

Downnload chntpw tool

Create bootable USB recovery disk.

Unzip to the USB root directory.

Run command prompt (run as administrator).

Type F:syslinux.exe -ma F: where F indicates your USB drive.


Now USB is ready to use.

Boot USB from the locked computer


After booting dont press any key , it will automatically detect partition and prints list of partition.

Press D (Automatically start disk drivers)


Type 1 (select your windows partition number)


Press enter (will detect windows directory))


Type 1 (password reset))


Type 1 (edit user data and password)


Type user name (example as in screen administrator)


Type 1 (clear user password)


Password cleared…..      Type  !    to quit


Type q (to quit)


Type y (about to write to disk)


Type q (to quit)


Type n (to exit)


Restart your computer and change the blank administrator password in windows


BIOS Password Removal

Some Users forget BIOS password or some may purchase computer from a friend and he is out of country, here are some steps to reset password.

Reset BIOS password using Hardware(two methods)

  1. a) Reset BIOS password removing CMOS battery
  2. b) Reset BIOS password using Jumper

Reset BIOS password using DOS

Reset BIOS password using Software

Reset BIOS password using Backdoor BIOS Password

Reset BIOS password using Hardware


Two methods: first is by removing CMOS battery, second by jumper in motherboard. Many of the desktop computers motherboard has a small coin sized CMOS battery. They store password and other settings. Once CMOS battery is removed the entire password and settings are lost and they are reset to factory defaults.

Reset BIOS password removing CMOS battery

Step 1 power off your computer and unplug power cable.

Step 2 open computer cover.

Step 3 locate coin sized battery.

Step 4 using flat screw driver push the battery lock to lift battery.

Step 5 remove battery and wait for half an hour to discharge.

Step 6 fix back battery, computer cover and power cable and power on computer.

Step 7 you will get CMOS checksum error and the settings will be restored to factory defaults.

Step 8 go to ths BIOS setup program by pressing F2 or delete or as per brand it varies and save settings . now your computer is without password.

Reset BIOS password using Jumper

Some desktop computers come with CMOS battery soldered to its motherboard. Use the jumper to clear settings.

Step 1 power off your computer and unplug power cable.

Step 2 locate the jumper as labeled as CLR, CLEAR, CLEAR CMOS, etc shown in the figure above. The location varies from computer to computer brands.

Step 3 there will be either 3 or 2 pins, if it is 2 pins insert the jumper in those 2 pins, if it has 3 pins remove the jumper and join the center pin to the opposite pin. If the jumper joins center pin to left pin, then remove it and join center pin to right pin or vice versa.

Step 4 wait for few seconds and re fix the jumper to its original position

Step 5 you will get CMOS checksum error and the settings will be restored to factory defaults.

Step 6 go to ths BIOS setup program by pressing F2 or delete or as per brand it varies and save settings . now your computer is without password.

Reset BIOS password using DOS

Step 1 create a DOS system disk.

Step 2 copy “debug” command from DOS or windows directory to the system disk.

Step 3 boot the computer from the system disk

Step 4 at command prompt type debug and enter you will see a “-“ blinking.

Step 5 type o 70 2E and enter

Step 6 type o 71 FF and enter

Step 7 type q and enter

Step 8 remove the system disk and reboot the computer, unplug power cable and re plug it, power ON your computer and settings reset.

The character “ o “ in the above commands is English alphabet “o” and not the number 0, it outputs the value to IO ports, The number 70 and 71 are port numbers which are used to access CMOS memory. FF – tells CMOS that there is an invalid checksum and it resets the CMOS settings as well as BIOS password.

Reset BIOS password using Software

CmosPWD application that can be used to retrieve and decrypt the BIOS password. It also provides backup, restoral, and erasing capabilities.

Works with the following BIOS * ACER/IBM BIOS * AMI BIOS * AMI WinBIOS 2.5 * Award 4.5x/4.6x/6.0 * Compaq (1992) * Compaq (New version) * IBM (PS/2, Activa, Thinkpad) * Packard Bell * Phoenix 1.00.09.AC0 (1994), a486 1.03, 1.04, 1.10 A03, 4.05 rev 1.02.943, 4.06 rev 1.13.1107 * Phoenix 4 release 6 (User) * Gateway Solo – Phoenix 4.0 release 6 * Toshiba * Zenith AMI

Step 1 Download & extract to a folder. Extract to a folder “ cmos “.

Step 2 To work on CMOS memory, ioperm need to be installed and running. ioperm gives direct port I/O access for specified ports to user-mode process (ring 3) using Ke386SetIoAccessMap and Ke386IoSetAccessProcess kernel functions.

Step 3 Log on to Windows as Administrator.

Step 4 Run command prompt

Step 5 go to the directory d:\cmos\windows by using command “ cd\” then go to “d:” where the cmos directory is present. Then type cd cmos then press enter key then type cd windows and press enter key

Step 6 when you are in d:\cmos\windows then type “ioperm.exe –i” hit enter.

Step 7 to start ioperm service type “net start ioperm” hit enter.

Step 8 type “Cmospwd_win.exe /k” hit enter , the below commands will appear in the prompt 1 – Kill cmos 2 – Kill cmos (try to keep date and time) 0 – Abort Choice :

Step 9 Type 1 and hit Enter to clear cmos.


now the password is reset and you will have to insert a new password and save it.

Reset BIOS password using Backdoor BIOS Password

Many BIOS manufacturers have provided backdoor passwords that can be used to access the BIOS setup in the event you have lost your password. These passwords are case sensitive, so you may wish to try a variety of combinations. WARNING: Some BIOS configurations will lock you out of the system completely if you type in an incorrect password more than 3 times. Read your manufacturers documentation for the BIOS setting before you begin typing in passwords.

Award BIOS backdoor passwords:

aLLY Condo PINT 01322222
ALLY d8on pint 589589
aPAf djonet SER 589721
_award HLT SKY_FOX 595595
AWARD_SW J64 SYXZ 598598
AWARD?SW J256 syxz
AWARD SW J262 shift + syxz

AMI BIOS Backdoor Passwords:


Phoenix BIOS Backdoor Passwords:


Misc. Common Passwords

ALFAROME BIOSTAR biostar biosstar
CMOS cmos LKWPETER lkwpeter
setup SETUP Syxz Wodj

Other BIOS Passwords by Manufacturer

Manufacturer Password
VOBIS & IBM merlin
Dell Dell
Biostar Biostar
Compaq Compaq
Enox xo11nE
Epox central
Freetech Posterie
IWill iwill
Jetway spooml
Packard Bell bell9
Siemens SKY_FOX
Toshiba Toshiba

Toshiba BIOS

Most Toshiba laptops and some desktop systems will bypass the BIOS password if the left shift key is held down during boot


Press both mouse buttons repeatedly during the boot

Important Linux Commands

Important Linux Commands

ls [options] [files]

If you run ls without any additional parameters, the program lists the contents of the current directory in short form.


Detailed list


Displays hidden files

cp [options] source target

Copies source to target.


Waits for confirmation, if necessary, before an existing target is overwritten


Copies recursively (includes subdirectories)

mv [options] source target

Copies source to target then deletes the original source.


Creates a backup copy of the source before moving


Waits for confirmation, if necessary, before an existing targetfile is overwritten

rm [options] files

Removes the specified files from the file system. Directories are not removed by rm unless the option -r is used.


Deletes any existing subdirectories


Waits for confirmation before deleting each file

ln [options] source target

Creates an internal link from source to target. Normally, such a link points directly to source on the same file system. However, if ln is executed with the -s option, it creates a symbolic link that only points to the directory in which source is located, enabling linking across file systems.


Creates a symbolic link

cd [options] [directory]

Changes the current directory. cd without any parameters changes to the user’s home directory.

mkdir [options] directory

Creates a new directory.

rmdir [options] directory

Deletes the specified directory if it is already empty.

chown [options] username[:[group]] files

Transfers ownership of a file to the user with the specified username.


Changes files and directories in all subdirectories

chgrp [options] groupname files

Transfers the group ownership of a given file to the group with the specified group name. The file owner can change group ownership only if a member of both the current and the new group.

chmod [options] mode files

Changes the access permissions.

The mode parameter has three parts: group, access, and access type. group accepts the following characters:







For access, grant access with + and deny it with .

The access type is controlled by the following options:






Execute—executing files or changing to the directory


Setuid bit—the application or program is started as if it were started by the owner of the file

As an alternative, a numeric code can be used. The four digits of this code are composed of the sum of the values 4, 2, and 1—the decimal result of a binary mask. The first digit sets the set user ID (SUID) (4), the set group ID (2), and the sticky (1) bits. The second digit defines the permissions of the owner of the file. The third digit defines the permissions of the group members and the last digit sets the permissions for all other users. The read permission is set with 4, the write permission with 2, and the permission for executing a file is set with 1. The owner of a file would usually receive a 6 or a 7 for executable files.

gzip [parameters] files

This program compresses the contents of files using complex mathematical algorithms. Files compressed in this way are given the extension .gz and need to be uncompressed before they can be used. To compress several files or even entire directories, use the tar command.


Decompresses the packed gzip files so they return to their original size and can be processed normally (like the command gunzip)

tar options archive files

tar puts one or more files into an archive. Compression is optional. tar is a quite complex command with a number of options available. The most frequently used options are:


Writes the output to a file and not to the screen as is usually the case


Creates a new tar archive


Adds files to an existing archive


Outputs the contents of an archive


Adds files, but only if they are newer than the files already contained in the archive


Unpacks files from an archive (extraction)


Packs the resulting archive with gzip


Compresses the resulting archive with bzip2


Lists files processed

The archive files created by tar end with .tar. If the tar archive was also compressed using gzip, the ending is .tgz or .tar.gz. If it was compressed using bzip2, the ending is .tar.bz2.

locate patterns

This command is only available if you have installed the findutils-locate package. The locate command can find in which directory a specified file is located. If desired, use wild cards to specify filenames. The program is very fast, because it uses a database specifically created for the purpose (rather than searching through the entire file system). This very fact, however, also results in a major drawback: locate is unable to find any files created after the latest update of its database. The database can be generated by root with updatedb.

updatedb [options]

This command performs an update of the database used by locate. To include files in all existing directories, run the program as root. It also makes sense to place it in the background by appending an ampersand (&), so you can immediately continue working on the same command line (updatedb &). This command usually runs as a daily cron job (see cron.daily).

find [options]

With find, search for a file in a given directory. The first argument specifies the directory in which to start the search. The option -name must be followed by a search string, which may also include wild cards. Unlike locate, which uses a database, find scans the actual directory.

Commands to Access File Contents

file [options] [files]

With file, detect the contents of the specified files.


Tries to look inside compressed files

cat [options] files

The cat command displays the contents of a file, printing the entire contents to the screen without interruption.


Numbers the output on the left margin

less [options] files

This command can be used to browse the contents of the specified file. Scroll half a screen page up or down with PgUp and PgDn or a full screen page down with Space. Jump to the beginning or end of a file using Home and End. Press Q to exit the program.

grep [options] searchstring files

The grep command finds a specific search string in the specified files. If the search string is found, the command displays the line in which searchstring was found along with the filename.


Ignores case


Only displays the names of the relevant files, but not the text lines


Additionally displays the numbers of the lines in which it found a hit


Only lists the files in which searchstring does not occur

diff [options] file1 file2

The diff command compares the contents of any two files. The output produced by the program lists all lines that do not match. This is frequently used by programmers who need only to send their program alterations and not the entire source code.


Only reports whether the two files differ


Produces a unified diff, which makes the output more readable

File Systems

mount [options] [device] mountpoint

This command can be used to mount any data media, such as hard disks, CD-ROM drives, and other drives, to a directory of the Linux file system.


Mount read-only

-t filesystem

Specify the file system, commonly ext2 for Linux hard disks, msdos for MS-DOS media, vfat for the Windows file system, and iso9660 for CDs

For hard disks not defined in the file /etc/fstab, the device type must also be specified. In this case, only root can mount it. If the file system needs to also be mounted by other users, enter the option user in the appropriate line in the /etc/fstab file (separated by commas) and save this change. Further information is available in the mount(1) man page.

umount [options] mountpoint

This command unmounts a mounted drive from the file system. To prevent data loss, run this command before taking a removable data medium from its drive. Normally, only root is allowed to run the commands mount and umount. To enable other users to run these commands, edit the /etc/fstab file to specify the option user for the relevant drive.

7.12.2 System Commands

The following section lists a few of the most important commands needed for retrieving system information and controlling processes and the network.

System Information

df [options] [directory]

The df (disk free) command, when used without any options, displays information about the total disk space, the disk space currently in use, and the free space on all the mounted drives. If a directory is specified, the information is limited to the drive on which that directory is located.


Shows the number of occupied blocks in gigabytes, megabytes, or kilobytes—in human-readable format


Type of file system (ext2, nfs, etc.)

du [options] [path]

This command, when executed without any parameters, shows the total disk space occupied by files and subdirectories in the current directory.


Displays the size of each individual file


Output in human-readable form


Displays only the calculated total size

free [options]

The command free displays information about RAM and swap space usage, showing the total and the used amount in both categories.


Output in bytes


Output in kilobytes


Output in megabytes

date [options]

This simple program displays the current system time. If run as root, it can also be used to change the system time. Details about the program are available in the date(1) man page.


top [options]

top provides a quick overview of the currently running processes. Press H to access a page that briefly explains the main options for customizing the program.

ps [options] [process_ID]

If run without any options, this command displays a table of all your own programs or processes—those you started. The options for this command are not preceded by hyphen.


Displays a detailed list of all processes, independent of the owner

kill [options] process_ID

Unfortunately, sometimes a program cannot be terminated in the normal way. In most cases, you should still be able to stop such a runaway program by executing the kill command, specifying the respective process ID (see top and ps). kill sends a TERM signal that instructs the program to shut itself down. If this does not help, the following parameter can be used:


Sends a KILL signal instead of a TERM signal, bringing the specified process to an end in almost all cases

killall [options] processname

This command is similar to kill, but uses the process name (instead of the process ID) as an argument, killing all processes with that name.


ping [options] hostname_or_IP address

The ping command is the standard tool for testing the basic functionality of TCP/IP networks. It sends a small data packet to the destination host, requesting an immediate reply. If this works, ping displays a message to that effect, which indicates that the network link is basically functioning.


Determines the total number of packages to send and ends after they have been dispatched (by default, there is no limitation set)


flood ping: sends as many data packages as possible; a popular means, reserved for root, to test networks


Specifies the interval between two data packages in seconds (default: one second)

host [options] hostname [server]

The domain name system resolves domain names to IP addresses. With this tool, send queries to name servers (DNS servers).

ssh [options] [user@]hostname [command]

SSH is actually an Internet protocol that enables you to work on remote hosts across a network. SSH is also the name of a Linux program that uses this protocol to enable operations on remote computers.


passwd [options] [username]

Users may change their own passwords at any time using this command. The administrator root can use the command to change the password of any user on the system.

su [options] [username]

The su command makes it possible to log in under a different username from a running session. Specify a username and the corresponding password. The password is not required from root, because root is authorized to assume the identity of any user. When using the command without specifying a username, you are prompted for the root password and change to the superuser (root). Use su – to start a login shell for a different user.

halt [options]

To avoid loss of data, you should always use this program to shut down your system.

reboot [options]

Does the same as halt except the system performs an immediate reboot.


This command cleans up the visible area of the console. It has no options.

Get help with Windows 10 upgrade and installation errors


This page lists the most common upgrade and installation errors and a some things you can try to fix them. If you continue having problems upgrading or installing Windows 10, contact Microsoft support.

Error What it means and how to fix it
0x80073712 A file needed by Windows Update is likely damaged or missing.
0x800F0923 This might indicate that a driver or other software on your PC isn’t compatible with the upgrade to Windows 10. For info about how to fix this problem, contact Microsoft support.
0x80200056 This could mean that the upgrade process was interrupted because you accidentally restarted your PC or signed out of your PC. Try upgrading again and make sure your PC is plugged in and stays turned on.
This error might mean that your PC couldn’t connect to the Windows Update servers. If you’re using a VPN connection to connect to a work network, disconnect from the network and turn off the VPN software (if applicable) and try upgrading again.
The error could also mean there isn’t enough free space in the System Reserved partition. You might be able to fix this problem by using third-party software to increase the size of the System Reserved partition.
Error: We couldn’t complete the updates. Undoing changes. Don’t turn off your computer.
Error: Failure configuring Windows Updates. Reverting changes.
These are generic errors that might appear any time a Windows update fails. You’ll need to determine the specific error code to investigate how to best resolve this problem.
You can find the error code for the failed update by viewing your update history. Look for the update that wasn’t installed, note the error code, and then contact Microsoft support.

To view your update history in Windows 8.1:

  • Open Windows Update by swiping in from the right edge of the screen (or, if you’re using a mouse, pointing to the lower-right corner of the screen and moving the mouse pointer up), select Settings  > Change PC settings > Update and recovery View your update history.
To view your update history in Windows 7:
  • Select the Start button
    Start button icon

    . In the search box, type Update, and then, in the list of results, Select Windows Update > View update history.

Error: The update isn’t applicable to your computer. This error might mean that your PC doesn’t have the required updates installed. Check to make sure that all important updates are installed on your PC before you try upgrading.
0xC1900208 – 0x4000C This could indicate that an incompatible app installed on your PC is blocking the upgrade process from completing. Check to make sure that any incompatible apps are uninstalled and then try upgrading again.
0xC1900200 – 0x20008
0xC1900202 – 0x20008
This may signify that your PC doesn’t meet the minimum requirements to download or install the upgrade to Windows 10.
0x80070070 – 0x50011
0x80070070 – 0x50012
0x80070070 – 0x60000
This likely indicates that your PC doesn’t have enough space available to install the upgrade. Free some space on the drive and try again.