If you computer is infected with Virus and you are fed of problem creating with virus and you don't want to spend buying Antivirus then here is best solution by Microsoft.

This Antivirus is Portable in nature that means you need not to install,You can carry in your pen drive and you can scan as when needed.
You should check out Microsoft Safety Scanner. This is a free antivirus software, always updated with the latest definitions, and requires no installation - all you need to do is copy the program executable msert.exe to an infected computer and double-click that file. If it detects a problem, the infected files will be quarantined.The program expires after 10 days but you can always re-download it with the updated virus definitions.

Microsoft Safety Scanner is available as a free download for both 32-bit and 64-bit version of Windows. You may use on Windows XP, Vista or Windows 7 machines and, unlike Microsoft’s other antivirus software, Safety Scanner doesn’t perform a check for genuine Windows.

1. Last week I came across a virus with new folder.exe and regsrv.exe and autorun.inf. I was searching for suitable solution for autorun.inf but I didnt get any proper solution for long time but Today I found a USB virus removal tool which is quit effective. This will help to remove above said virus .Click here to find the Download
2. Here is one more method I am going to tell you this is manual process. Follow this process if you can't remove using above tool. In most of the case this virus will disable regedit and task manager.  I am also going to tell you how to enable REGEDIT and TASKMANGER . To enable regedit just Click Start, Run and type this command HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableRegistryTools /t REG_DWORD /d 0 /f    To enable task manager Click Start, Run and type this command REG add HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\System /v DisableTaskMgr /t REG_DWORD /d 0 /f
   1. Search for autorun.inf file. It is a read only file so you will have to change it to normal by right clicking the file , selecting the properties and un-check the read only option
   2. Open the file in notepad and delete everything and save the file.
   3. Now change the file status back to read only mode so that the virus could not get access again.
   4. 
   5. Click start->run and type msconfig and click ok
   6. Go to startup tab look for regsvr and uncheck the option click OK.
   7. Click on Exit without Restart, cause there are still few things we need to do before we can restart the PC.
   8. Now go to control panel -> scheduled tasks, and delete the At1 task listed their.

What will happen if your System is infected with viruses and the Antivirus you had installed failed to protect? In several cases, the virus may also disable any anti virus programs that you may try to run to disinfect.

Can we use a portable anti virus program which is installed in a USB Flash drive to scan our computer? The answer is a definite Yes! This is an easy way to disinfect an infected computer usiSB disk or your iPod.

ClamWin has come up with such an anti virus application. ClamWin Portable is a popular ClamWin antivirus packaged as a portable app, so you can take your anti virus with you to scan files on the go. You can place it on your USB flash drive, iPod, portable hard drive or a CD and use it on any computer, without leaving any personal information behind.

Hoping to dispel fears about the vulnerability of Windows to viruses and other malware, Microsoft released a trial version of a n
ew free security package called Microsoft Security Essentials.

The software is designed to replace the Windows Defender tool that Microsoft released in 2007, but which was widely derided as being inadequate to protect computers from the constant and ever-evolving threats posed by hackers.

Microsoft has been widely criticised for failing to include free and effective security software in its Windows operating systems, which are targeted far more intensely by malicious software than the rival Linux and Apple systems.

The world's largest software company said that Microsoft Security Essentials is available to the first 75,000 subscribers in the US, Israel, Brazil and China. The software is meant to run in the background, without constantly bombarding users with security alerts or using a lot of system resources.

A full version of the software is expected to become available in September.