Need help : Unable to gain access to a hard disk.

Hello. I am using Windows vista home basic 32bit Os. I clicked the
security tab in the properties dialog box of a hard drive and denied
access to it for all users. Later when i opened the same, i could not
find the security tab in the properties. But the properties of other
hard disks have the security tab. Even being as an admin, i cannot find
the security tab.
Can anybody suggest me how to allow access to this hard disk ?


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kamma