"I have a second computer with only user account. 
But  I changed its password a long time ago, and now I forgot it. So now
 the problem  is I cannot log into the PC with other user account. I am 
wondering if there is  a way to bypass that password. Can someone teach 
me please?"
Being  denied access to Windows XP computer for XP 
password forgotten has always been  a hot issue among pc users. I am 
sure many people have racked their brains for  a few moments, trying to 
remember what that word combination is the exact  password. Usually, to 
re-gain access to your PC by thinking of what the  password is, is 
always time-consuming and in vain at last. This could never be a  smart 
way. So, now you may want to look for an easier and quicker solution to bypass Windows XP password
 that won't take your hours or even days to figure out. Fortunately, 
there are  such solutions indeed, and below are 2 such solutions to 
bypass XP user login password.
Solution 1: Use Windows XP built-in Administrator  account.
If you are an XP user, and you have forgotten the password for your only user account on the XP machine, you may have neglected the Windows XP built-in Administrator account. You cannot see this account on your computer since it is hidden by default. But now you can easily unhide it to help you bypass XP admin password because this built-in Admin has no password protected by default, but has highest privileges over the whole PC. Follow the below steps to unhide this admin account and recover forgotten Windows XP password next:
Step1: Start your computer and press "Ctrl+Alt+Delete" twice when you see Windows Login screen.
Step2: Type Administrator in username box and leave the password column blank.
Step3: Now you have successfully gained access to your XP PC again and later you can freely change or remove your forgotten Windows XP password from: "Start->Control Panel->User Accounts".
If you are an XP user, and you have forgotten the password for your only user account on the XP machine, you may have neglected the Windows XP built-in Administrator account. You cannot see this account on your computer since it is hidden by default. But now you can easily unhide it to help you bypass XP admin password because this built-in Admin has no password protected by default, but has highest privileges over the whole PC. Follow the below steps to unhide this admin account and recover forgotten Windows XP password next:
Step1: Start your computer and press "Ctrl+Alt+Delete" twice when you see Windows Login screen.
Step2: Type Administrator in username box and leave the password column blank.
Step3: Now you have successfully gained access to your XP PC again and later you can freely change or remove your forgotten Windows XP password from: "Start->Control Panel->User Accounts".
Solution 2: Use Windows Password Recovery Enhance.
Windows Password Recovery Enhance is a professionally third-party application made for resetting any forgotten or lost Windows password on all Windows-based PCs. All you need to bypass Windows XP login password with this tool, are just 3 steps only: download the software>>burn a disk>>reset password. Below are the detailed steps:
Step1: Download, install and run Windows Password Recovery Enhance on any accessible computer.
Step2: Burn a bootable password recovery CD/DVD/USB with this software. Insert a blank CD/DVD or USB flash drive to the accessible PC and click “Burn” button in the main interface to start burning a bootable password recovery disk.
Step3: Start to reset Windows XP password. First insert the burned disk to the target computer and later set this computer boot from CD/DVD/USB in BIOS. After that, you can start to unlock the lost Windows XP password for your locked PC with 3 clicks of button only.
Windows Password Recovery Enhance is a professionally third-party application made for resetting any forgotten or lost Windows password on all Windows-based PCs. All you need to bypass Windows XP login password with this tool, are just 3 steps only: download the software>>burn a disk>>reset password. Below are the detailed steps:
Step1: Download, install and run Windows Password Recovery Enhance on any accessible computer.
Step2: Burn a bootable password recovery CD/DVD/USB with this software. Insert a blank CD/DVD or USB flash drive to the accessible PC and click “Burn” button in the main interface to start burning a bootable password recovery disk.
Step3: Start to reset Windows XP password. First insert the burned disk to the target computer and later set this computer boot from CD/DVD/USB in BIOS. After that, you can start to unlock the lost Windows XP password for your locked PC with 3 clicks of button only.
Yep,  that’s all for the steps on how to bypass XP password.
 Which  one should I choose? This is according to the situation you are 
in. If you  haven’t changed any settings for the built-in Administrator 
account on your PC,  then solution one can be your best choice. While 
bypassing XP user login  password with Windows Password Recovery Enhance
 is also a good choice since its  created password recovery disk can be 
useful whenever you forgot or lost  password.
Article source: http://www.blog.windowspasswordrecovery.net/bypass-windows-xp-password.html
 
