Help needed to boot vista


Hello, i have windows xp and vista installed on my pc. Both are installed in different hdd's . Xp was installed first and then vista was installed on other hard drive. I the hard drive in which xp is installed was giving errors and freezing, so i removed it. But now vista doesn boot even though its on a different hard drive. I tried to change the boot priority of the hard drive in which vista is installed in BIOS, but the problem persists. I get a message "Error loading os". How can i fix this problem?
Hi nithin,

Boot from your Vista DVD and select "Startup Repair"

Vista will take care of the rest.