I’ve been using Windows 7 fairly regularly on one of my machines for the past month or so. One thing I noticed is that the default password settings for Windows 7 include the fact that password expire after 42 days. Since most home users will never change their default settings, this setting will likely become a de-facto standard. However, the default settings also have a password history of zero (no remembered passwords), and a minimum age of zero as well. This means that every home user, when prompted to change their Windows password, will simply change it to the password they had initially, making this setting useless.
Actually, You can disable a Windows password policy by editing the Local Group Policy Editor. The policy editor is only available to Microsoft Windows 7 Ultimate, Enterprise and Professional users. The Local Group Policy Editor is part of the Microsoft Management Console and works as a snap-in to edit your computer and user configuration data and settings. You must be logged on as a Windows administrator to access and edit policies in the Local Group Policy Editor.
Log on as Administrator
1.Click on the "Start" button, and type "cmd" in search bar at the bottom and press "Enter."
2.Type "net user administrator /active:yes" without the quotations and press "Enter." Be sure to type the words exactly as shown, including spaces.
3.Click on the "Start" orb again and click the arrow next to "Shut Down" on the right-hand side. Click on "Log off" and choose the Administrator profile that shows up.
Open Policy Editor
1. Click on the circular "Start" and type "gpedit.msc" without the quotations in the search bar at the bottom. Press "Enter."
2. Click "Yes" if you get a message prompting you for your permission to access the program.
3. Right-click on the words "Default Domain Policy GPO" on the top left-hand panel, and then click on "Edit."
4. Double-click "Computer Configuration," "Windows Settings," "Security Settings," "Account Policies" and "Password Policy," in that order, from top to bottom.
5. Double-click on "Enforce password history" on the editor's right-hand panel under "Policy Setting," type 0 and click on "OK." Repeat this (by typing 0) for the "Maximum password age," "Minimum password age" and "Minimum password length."
6. Double-click "Password must meet complexity requirements" on the right-hand side under "Policy." Click on the "Disabled" option under "Policy Setting" and click on "OK."
7. Click on the "X" button in the upper right-hand corner. Your Windows password policy is now fully disabled.
Sometimes, if you can not log on with the admin password or you forgot Windows admin password ,how should you to disable the Windows 7 password policy? Well, in the beginning, you must reset Windows 7 admin password. Get more about Windwos 7 admin password recovery from: http://www.passwordunlocker.com/knowledge/forgot-windows-7-password.html