Install a good anti-virus would have to spend money and to the antivirus vendor issued a free version for one month after one month longer Antivirus can not update (no longer able to support from Antivirus vendors). If you Antivirus has expayed can not hope to re-install your anti-virus , despite being in first uninstall .but when you install another OS Anti-virus may be re-used, but this is not troublesome enough? .. Here’s the perfect solution but it is very effective to deal with the growing viral great OB basic logic. If there was a lot of rubbish what we may have to mop instead ?…. certainly not a good solution is that we brush first and then we mop or wipe the floor. Are you sure your computer has been 100% safe from viruses. although I have installed a good anti-virus and security updates may not be 100% of the virus.