Someone started controlling my computer over the Internet -- what happened?

There are "Trojan horse" type programs, such asBack OrificeandNetbus, that could cause the behavior you are describing. Both BO and Netbus are Windows 95/98 applications designed to allow other people to access your machine (generally for malicious purposes) over the Internet.

In order for anyone to use BO on your machine, you have toinstall the server side of the application. This is normally done by getting you to download an application or by sending the server EXE to you in ane-mailmessage and hoping you execute it. This is why it is called aTrojan horse——你必须有意识或者无意识th运行e EXE to install the server -- it does not propagate itself like a virus (seeHow Computer Viruses Workfor a description of Trojans and viruses). Once you execute the server EXE, the server is installed and will start running automatically every time you turn on your computer.

With the server installed, an evil-doer can run the BOclient programand control your computer remotely, running programs, erasing files... Obviously, this is not a good thing. It is easy todetectBack Orifice either manually or with software.

These links will help you learn more: