Disconnect the device from the internet
Back up important files to an external drive or cloud account
Boot into Safe Mode
Run a full scan with updated antivirus or anti-malware software
Remove or quarantine detected threats
Uninstall suspicious programs and browser extensions
Clear temporary files and browser data
Check startup items and disable unknown entries
Update the operating system and all installed software
Change passwords from a clean device
Enable two-factor authentication on important accounts
Restore the system from a clean backup if needed
Reset the browser or reinstall the operating system if infection persists