Host file in Windows, edit and restore the file

The hosts file is a vulnerable place in the Windows operating system. This file is the purpose of the attack almost for all viruses and Trojans, who manage to invent the computer. In this article I will explain what the host file is, where it is, for what is used and how it can be recovered after the computer infection with viruses.

What is the host file

The purpose of this file is to keep a list of apps and appropriate IP addresses. The operating system uses this list to convert areas into IP addresses and vice versa.

When entering a URL of a site in the browser, a request occurs to convert domain into the IP address. Now this conversion makes the service called DNS. But, at the beginning of the internet development, the host file was the only possibility of connecting the symbolic name (domain) to an IP address.

Even now this file has a direct impact on the transformation of the symbolic name. If we insert the host file an entrance, which will connect the IP address to the domain, this entrance will work without problems. These inputs and virus developers, trojans and other dangerous programs are used.

As for the file structure, the host file is a type of normal text file without extension. That is, this file is not called the hosts.txt, but simply host. To publish it, the Notpad text editor can be used.

The standard host file contains some lines, which start with the «#» character. These lines are not taken into consideration by the operating system.

In addition, the standard host file contains the entrance «127.0.0.1 Localhost». This item means that when you contact the symbolic name Localhost, you will turn to your computer.

Changing the host file

There are two ways to benefit from the changes made to the host file. First of all, with its help we can block access to the sites and servers of antivirus programs.

For example, by infecting the computer, the virus adds to the «127.0.0.1 kaspersky.com» entrance file. Trying to open the Kaspersky.com website, the Operating System SA connected to the IP address 127.0.0.1. Of course it's a wrong IP address. This will lead to the fact that access to this site will be completely blocked. As a result, the computer of the computer virus will not be able to update or download the antivirus.

In addition, virus developers can use other techniques. By adding input to the host file, they can reduce users to false sites.

For example, by infecting the caundulator, the virus adds to the host 'host «90.80.70.60 Facebook.com». Where «90.80.70.60» is the address of the attacker's server. As a result, trying to access the site, you will reach a site that looks like the same, but it is on the attacker's server. That following these actions can obtain access, password data and other personal information.

Where is the host file

Depending on the version of the Windows operating system, the host file can be in different folders. For example, in Windows XP, Windows Vista, Windows 7 or Windows 8, the file is in the folder Windows System32 driver etc .

In Windows NT and Windows 2000 operating systems This file is in the folder Winnt System32 Driver etc .

Restoration of the host file

Many users, who have been viruses, asks, where you can download the host file. You don't have to search and download the host file. It can be restored, to do this opens the text editor and eliminate everything except the «127.0.0.1 Localhost» line. This will allow you to unlock access to all sites and update the antivirus.

1. Open the folder where it is the host file. In order not to waste time bending, we can call a trick. Press the key combination Windows+RTo open the menu «Run». In the open window insert the order «%Systemroot% System32 Driver etc.» And press the OK button.
2. The folder in which the host file will open will open.
3. So you have to make a copy of the current file (if something does not go well). If the host file exists, it renames it only in hosts.old. If the host file is missing from this folder, it is possible to jump on this step.
4. Create a new host file. To do this, press with the right mouse button in an empty place in the folder etc. And select the point «Create a text document».
5. After creating the file, you will have to rename it in the hosts. During the redenomination, a warning window will appear, which the file will be saved without extension. Close the window with notice by pressing the OK button.
6. After creating the file, you can write it. To do this, it opens the file with the Notpad text editor.
7. For Windows XP and Windows Server 2003 they add the line «127.0.0.1 Localhost».
8. For Windows Vista, Windows Server 2008, Windows 7 and Windows 8 add two lines «127.0.0.1 Localhost» Si «:: 1 Localhost»