I had this problem before and you should know that its really easy and simple to solve it whether you are installing sql server on vista or seven you should run the installation as administrator another suggestion: if you are the only user on this pc you may find it useful to make your default user the administrator because lots of things on vista and seven really needs administrator previliges to wrok the right way and if you dont have good experience and afraid of missing something just keep the User Account Control turned on and whenever you will do something that might need a permission it will show you a confirmation message even if you are using the adminitrator account I hope it helped :-)