I just purchased a new desktop with Vista home premium. While I was just powering up the computer, it show the installation screen but I accidentally knocked the power off for the computer. After I turned it back on, I keep getting a message saying that "windows installation was not complete or an error occurred, please restart to start installation again", after everytime I restart the message just keeps on popping up asking to restart everytime. Is there any way I can fix this problem, and start the windows installation? I have not done anything to this computer yet, no recovery cd, nothing. Please help.

What kind of computer is it?

Acer Aspire

Acer has built in recovery The easiest thing to do would be to run the recovery. {ALT}{F10} is the keyboard combination to access the recovery program. Start hitting these keys when you see the acer splash screen when you first turn on the computer. The other alternative is to try this http://www.bleepingcomputer.com/tutorials/tutorial148.html if the machine came with the vista disc for upgrade.