When run, it shows nothing important on the screen imitating hard disk formatting and Flash BIOS corruption. At the same time, it copies itself to the Windows directory and modifies the Windows registry to be run upon startup. It also renames WIN.COM to WIR.COM so Windows cannot be started normally anymore. Even if you rename WIR.COM to WIN.COM and start Windows, the trojan will repeat its activities and shutdown Windows. The trojan also modifies some Windows settings in the registry. The only way to get rid of it is to manually delete LOVEYOU.EXE from the Windows directory (from DOS prior to Windows startup) and then rename WIR.COM back to WIN.COM.