Hi,
Please do try these troubleshooting steps that may help.
- Start by loading the laptop in Safe Mode and see if it will work there.
- While the laptop is booting up, repeatedly press on F8 until it loads Advanced Boot Options.
- Select Safe Mode then press Enter and once in the login screen do try logging in.
- If it will let you login do run System Restore, restore the laptop to an earlier date or time before the problem even happened.
- Here's how to run System Restore:
http/windows.microsoft.com/en-ph/windows7/restore-system-files-and-settings
- If System Restore will not work, do contact Sony for more information about password related concerns.