I purchased iolo System Mechanic 9.5 to replace Norton System Works 2008, after reading many reviews (apparently old reviews). Norton products quality has steadily gone down since Mr. Norton sold the company in 2004. Iolo System Mechanic 9.5 installed on 2 of my 3 computers fine running Microsoft Windows XP. But, on the third computer running Microsoft Windows XP, the install stopped after entering the registration key without any error messages. This happened many times, no matter what I tried. I then found out that iolo has no phone support and their e-mail support is in India. After many slow emails over 2 weeks and doing everything they suggested (which I had already done on my own), I guess they gave up, because they stopped answering any of my emails... I removed iolo System Mechanic 9.5 from my computers and threw it away. I bought Advanced System Optimizer 3.0 and installed it on all 3 of my computers running Microsoft Windows XP and it installed and works perfect. Note that on the 2 computers that System Mechanic 9.5 was installed on before, Advanced System Optimizer 3.0 found much more spyware (98 & 139 infections) right after System Mechanic 9.5 had run and optimized the 2 computers. DO NOT BUY OR USE ANY IOLO PRODUCT FROM NOW ON OR YOU WILL REGRET IT, I DID...