Ok so, I've spent the entire day researching this problem, and I have yet to find a solution other than "wait for it to finish preparing the backup". And since my time machine has been preparing backup for a little over 36 hours, I think I've waited enough. Does anyone have a concrete solution to this problem? I've read official apple troubleshoot documents, other forums' suggestions (repairing disk permission, deleting everything off the harddrive and starting fresh) and I just want to know if there is a concrete solution that I can do to stop wasting my time.