The trojan has a set of functions, such as control of the remote computer, obtaining someone else's Internet accounts, cracking and other. Most often people do not suspect that on their computer there is this program as download it, having taken for harmless, and sometimes and useful. It is difficult to find and cure a trojan, but it is necessary.
1. Decide on type of your trojan, that is understand what goes not so. There are three main types of trojans. The first is Mail Sender which is independently connected to accounts of Internet services (mail, ICQ and so forth) and sends the same trojan to all who are in contact lists. With its help other person can read your mail or withdraw, for example, money from your electronic account. Following, that is Backdoor, has approximately the same functions, only even with its help it is possible to manage the remote computer almost completely. For example, to delete or send files. At last, the last is Log Writer which reads out all information entered from the keyboard and writes it in a certain file which will be transferred to "owner" of a trojan later. The sense is made approximately by the same, as Mail Sender. You should not forget that trojans are not limited to three types, these are only the main!
2. Find the RegEdit program on the computer (for this purpose just enter its name in start-up or look to the address c:windowsRegEdit.exe).
3. In the register look at such directories as soft, windows, run, runonce and others regarding suspicious EXE files. In what section will help to look for a trojan to you what you did in the first point – definition with trojan type. If you are afraid to delete files, then just rename them and look what changed.
4. If cleaning of the register did not help, then it is possible to use the XRun or CTask utilities which will give the complete information about the programs started at present. It is also possible to look a dispecher of tasks, but it can be inefficient.
5. So, in fight against a trojan the main thing is an attentiveness and care. Be extremely accurate with net surfing and use qualitative antiviruses that the computer was not necessary to treat.