A. Forgot Acer Aspire Windows 7 password, we can break password with Acer Aspire password reset disk:
1. After wrong password prompt displays, click “OK” – “Reset Password”;
2. Insert the password reset disk into PC driver, click “Reset password" and the Password Reset Wizard will comes up, then “Next”;
3. Choose the targeted password reset disc from drop down box, and then click “Next”;
4. Input and confirm newly set password, then “Next” - “Finish”, close Password Reset Wizard.

Please note that the Acer Aspire one Windows 7 password reset disk can only be useful if we created it before we lost password. Now, it is not late to generate a password reset disk for our account. We also can share it with our much more friends!
Step 1. Power on Acer Aspire Windows 7 laptop and login;
Step 2. Insert prepared bootable USB Flash Drive;
Step 3. Click Start -> Control Panel -> User Accounts and Family Safety -> User Accounts -> Create a password reset disk -> Next;
Step 4. Choose the inserted Flash Drive and click “Next”;
Step 5. Input login password and click “Next”;
Step 6. Click “Finish” to exit once progress indicator displays 100% complete, and then remove the disk from laptop.

B. For Acer Aspire one XP password recovery, we can unlock password from Safe Mode:
With the default administrator account, we can use it to bypass lost Acer Aspire XP password quickly.
Step 1. Press “F8” when power on Aspire laptop;
Step 2. At Advanced Boot Options window, choose “Safe Mode” and press Enter;
Step 3. Choose and Click the “Administrator” account at the Windows logon screen;
Please note that if you’ve ever set this administrator password, you need input the password set before. If not, you should keep the “Password” blank.
Step 4. Click Start -> Control Panel - user accounts -> Select the account needed to reset password -> Input new password.

C. For Acer Aspire Windows Vista password unlock, we can use free tool – Ophcrack
We can download the Ophcrack and burn a password reset disk to remove Aspire one Windows Vista password!

D. For Acer Aspire one Windows Server domain password, the most efficient way is to refer to professional Windows Password Recovery Corporation:                 
Step 1. Download Windows Password Recovery Corporation and burn a CD/DVD/USB Flash Drive to retrieve forgotten Windows domain password;
Step 2. Set your locked PC to boot from CD/DVD/USB Flash Drive;
Step 3. Reset forgotten Windows domain password to new password with the burned CD/DVD/USB Flash Drive.

So if we forgot Acer Aspire password on Windows 7/XP/Vista, we will never worry about our precious pictures, files on PC, Acer Aspire one password recovery is easy for us!

source: http://windowspasswordrecovery.net/article/acer-aspire-password-reset.html