reinstalled Vista, now no XP


without thinking it through, I have reinstalled Vista on it's partition on C:.
Previously I had created dual boot Vista and XP with EasyBcd, both OS's on partitions on C: with Vista first and XP last.

Now there is an unallocated partition after Vista's and the loading screen has an entry for 'Old Windows...' as well as Vista and XP. Only Vista boots.

I thought I did well to set it up originally, but that was ages ago and I've lost it !
Any way back to dual boots after my befuddled thinking ?...

many thanks
Start>Right click on Computer>Manage>Disk Management

Take a screenshot of that and attach it to your post. This way we can see for ourselves what is going on and try to advise.
It looks like you have formatted your XP partition when you reinstalled Vista.
Did you previously use a 3rd party partition manager when you set up your dual boot, and let Vista reformat the disk this time ?
Vista uses the latest partition alignment standards for the modern generation of huge HDDs, and if your XP partition used the old standards, it might well have "disappeared".