cannot reinstall vista,partition problem!!

hi guys, i have a problem..
i did shrink a partition which operating system is installed, but after
restarting the computer(it is a laptop) i am unable to log on to vista..
i tried to reinstall vista, but my operating system partition seems as
unallocated, and there is also another unallocated partition that i
shrunk..
since the partitions are unallocated and not formatted as NTFS, i am
unable to install vista..
it gives an error (Error:0x8004240f) when i try to create a new
partition, and the delete button does not work for unallocated
partitions,. what can i do, please give a way to solution..


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tuaydin