First get rid of the viruses introduced into the computer. If your antivirus program failed the task and did not identify the infected files, use special software. To deal with problems better in safe mode. To put it in the computer, click on the "start" button and select "Off". In the new window, click "Reset".
When you start a new download of the operating system, press F8 and moving through the menu using the arrow keys, select "safe mode". Press the Enter key. Remember that when using the arrow the Num Lock must be off.
Run a virus scanner. Well proven curing utility Dr.Web CureIt! It can help you scan your PC, find the malicious software and to disinfect infected files or delete them. This utility acts as a single tool. By the way, when you run it automatically places the computer in safe mode, so when using it, rebooting the PC may not be required.
If the virus block the sites from antivirus software, download utility from a third party site, ask your friends download and send to you by mail the latest version or burn it on another computer to removable media. After infected files were found and defused, but the problem is not resolved, the options can be many.
For example, some viruses create in the registry entries and then you need to search for them and delete. To enter in the registry editor, click on the "start" button and select the Run command. In the blank row of the window that opens, type without any extra characters and symbols in regedit and click OK or press Enter. In the editor, select the branch and edit the appropriate key.
If the virus asks to send the code to the short number, you can try to contact your mobile operator and report it. In some cases, you will be able to give the code to deactivate the parasite. But sometimes it's easier not to spend time searching for a virus that changed a lot of files, and just reinstall the operating system with full formatting hard drive.