A user reported their PC being locked by a virus masquerading as a police notification demanding a fine. To address the issue, running Ubuntu can help, but it may not be sufficient on its own. Utilizing antivirus tools like AVG's Rescue CD or similar bootable antivirus software is recommended for effective virus removal. If another user account exists on the infected computer, logging in may allow access to files that are not yet infected. However, caution is necessary as the virus can mutate and infect all accounts. If the system is completely locked, removing the hard drive and scanning it on another computer is an option. Additionally, performing a system restore to a point before the infection may help if using Windows. Backing up data from Ubuntu and considering a complete hard drive wipe and reinstallation is also advised for thorough cleanup.