Viruses and Trojans are a very serious threat.Most of them manage anti-virus software, but sometimes the user is faced with a situation where due to penetrating a computer Trojan operating system is blocked.
Operating System typically block "Trojans extortionists."When infecting a similar Trojan horse operation of the computer is locked, a window appears prompting you to enter the code to unlock.This code is proposed to receive after sending a certain amount specified in the details of the report.
If you encounter this form of fraud, never go on about the extortionists and do not send money to them, if only because there is no guarantee that you will actually send the code.In addition, the user name, to send money, support and encourage this method of fraud.
In that case, if your computer has two operating systems (this option is very convenient and useful), boot into another operating system, and log on to websites of antivirus vendors.In them you will find many
of the existing codes to unlock.For example, take a look here: https://www.drweb.com/xperf/unlocker/
Even if the operating system was able to unlock the computer are traces of Trojan, which can cause some problems.Take advantage of free tools from vendors of antivirus software to clean your computer.For example, this: http://www.freedrweb.com/cureit/
If you do not have a second operating system or the ability to access the Internet from another computer, there is two options.First, the best - install a second OS.If you have two or more hard drives, install it on one of the free.If the disc one, break it into two using a utility Acronis Disk Director.You will need a utility that runs from the installation disk.By installing a second operating system, you will be able to rebuild the underlying operating system.
The second option involves the use of recovery Live CD - the disk with the operating system boots directly from the CD.Usually, it's a bit stripped down, but it is a workable version of Windows XP.Booting "beneath" you can visit the sites of the producers of anti-virus software and try to unlock the computer.
If, despite all attempts to unlock the operating system fails, there is one option - booting the second operating system, or the Live CD, to save all important data, then format the drive with a locked operating system and install it again.When formatting choose full formatting, headers and not clean.After installing the new operating system immediately install an anti-virus program and update its database.