For this post I will be basing my opinion on the computers overall performance being affected by viruses and spyware. This question is going to be answered differently by many technicians. Some technicians reinstall Windows at the first sight of a virus instead of trying to remove it. Other technicians may receive a computer that is completely infested and may spend hours upon hours trying to remove the virus only to realize they probably didn’t achieve much of a performance increase in the end.
I usually fall right in between. Computer viruses today are becoming more and more sophisticated which in turn makes them harder to detect and remove. This is why your computer’s security is vital. If a customer brings in their computer to me at the first sign that something is going wrong then it’s usually fixable without having to reinstall Windows. On the other hand, when a customer brings me a computer that has gradually gotten worse over a fair amount of time, then it is usually not worth it to try and manually remove all the viruses and spyware because in doing so you are most likely not going to see an increase in the computer’s performance. This is when a clean install of Windows is necessary.
If the customer has their operating system cd and their program cd’s then it’s almost a no brainer to go ahead with a reinstall if the machine is pretty bad off. They are going to see the biggest increase in performance this way. Basically it is like starting fresh which in most cases is never a bad thing. It also gives you the peace of mind that their machine is clean of viruses and spyware.
I recently received a customer’s computer in which I wish I did a clean install of Windows. They had multiple viruses and spyware on their system that were really rooted in. They were actually almost victims of identity theft because the viruses stole their banking passwords. In this specific case the customer did not have their operating system cd on them which left me no choice to try and manually clean the system. After spending several hours and a half of dozen scans later the machine “appeared” to be clean after every scan turned up nothing. I gave the computer back and several hours later they contacted me saying they still believed there was a problem with their browser although hijackthis showed nothing. Take note that some deleted viruses can actually rebuild themselves making them extremely difficult to remove. Anyway, since they had their OS cd I decided to play it safe and format their hard drive and reinstall the OS so I knew for sure I was giving them back a clean system.
**I just wanted to update this post to say that formatting the hard drive and reinstalling the OS is no longer 100% proof. According to an article on technibble, some rootkit viruses can now survive a format. Great…
Nicholas Catanoso
Catanoso Computing
http://www.catanosocomputing.com