How do I restore permissions in Vista, Administrator has no control over the C: drive?

I was changing the security settings for my C: drive to disallow the guest user to access it, unfortunately I must have done something wrong and it has backfired, I now cannot directly access the drive and I cannot change the security settings, I have tried on both my main account and the Admin user.How do I restore permissions in Vista, Administrator has no control over the C: drive?
Read this closelyHow do I restore permissions in Vista, Administrator has no control over the C: drive?
u will restore ur computer at the previous time when the problem is started.by using the following step first goto :





Start Menu ---%26gt; All Programs ---%26gt; Accessories ---%26gt; System Tools ---%26gt; System Restore





then choose the previous date when problem is started.and follow the instructions ur problem will solve after finishing the process and then restart.

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