To reset a forgotten Windows password on Acer computer, there are several free methods:
1. Reset Acer password with another admin account.
2. Reset Acer password with Windows password reset disk.
3. Reset Acer password in Safe Mode.
4. Reset Acer password with CMD.
5. Reset Acer password using "lusrmgr.msc"
More dtails you can found on other sites, it is easy to find.
Anothe tip: Recover Acer password with a Windows password recovery tool.
This method requires you to load a Windows password recovery program.
1. Install the program on another computer and create a password recovery disk with USB
2. Insert the disk to your laptop and set your laptop to boot from it.
3. All user accounts will be loaded, then you can reset any user password.
If you want to read more details: http://goo.gl/3ZNY5