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I tried to use "Erase free space" from CCleaner in Mac. I was not sure about how it would work. When the process started there was about 175 GB of space available, and when the space started to decrease I was very worried and cancelled the process.

Then again after reading in some forums that first the available space will decrease, then it will come back once the process is over, I again started the process. Finally now only 20 GB is available. I don't know what happened to rest of the available space.

Can anyone give me some ideas regarding what to do?

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"Erasing" free space means filling the drive with zeros and then deleting it in many cases (in windows they use a the defrag API instead). You could probably use a tool like grandperspective to visually inspect your used space and delete the files cccleaner has generated.

enter image description here click on a block of files, and hit delete to delete or reveal to open it in finder

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Hi, I used the tool you suggested and the results are as follows : Volume Size - 297 Gb , Size of scanned files - 71.7 Gb, Miscellaneous used space - 207 Gb. The thing is i understand the temporary files created by ccleaner are in the 207 gb space. But i dont know how to delete them :( – Atom May 4 '12 at 11:09
Please check this screen shot ![Miscellaneous space][2] [2]: – Atom May 4 '12 at 13:30
click on them, then hit reveal. that should throw you into finder, so you can work out what they are. – Journeyman Geek May 4 '12 at 14:41
Hi i can able to reveal other block of files except the miscellaneous space. I suppose this is where the temporary files are stored. How to reveal that particular space/block ? – Atom May 4 '12 at 15:19

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