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CCleaner Disk Wipe


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#1 OFFLINE AWimpyNiNjA

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Posted 17 March 2011 - 11:48 AM

So i just downloaded CCleaner and i love the product. I had one question about the disk wipe option.
How does the disk wipe go about wiping the drive? Does it write 0's or 1's to the drive?
If it writes 0's then its not going to do any more on 35 passes then 1 pass.
If its random or 1's then this is the best drive cleaner i've seen =).

#2 OFFLINE Augeas

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Posted 17 March 2011 - 04:43 PM

It uses binary zeroes. The last pass in a 35-pass write (according to CC's version of Gutmann) is also zeroes so the (apparent) end result is indeed the same. My opinion is that one pass is perfectly adequate anyway.

Out of interest, why do you think that random writes are better than zeroes?

#3 OFFLINE AWimpyNiNjA

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Posted 18 March 2011 - 03:12 PM

It uses binary zeroes. The last pass in a 35-pass write (according to CC's version of Gutmann) is also zeroes so the (apparent) end result is indeed the same. My opinion is that one pass is perfectly adequate anyway.

Out of interest, why do you think that random writes are better than zeroes?


After a clean pass of 1's, the random writes just decrease the chances even more of anyone trying to recover data from it,

#4 OFFLINE Alan_B

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Posted 18 March 2011 - 04:10 PM

If it writes 0's then its not going to do any more on 35 passes then 1 pass.
If its random or 1's then this is the best drive cleaner i've seen =).


Your first mistake is total failure to see what Wikepedia says about Gutmann :-
http://en.wikipedia..../Gutmann_method

Note firstly "writing a series of 35 patterns over the region to be erased"
There may be a sequence of 0's in one pass, but 34 other passes will be different.

Secondly note that 1's and 0's are actually +value and -value.
The disc does NOT receive maximum magnetism for a sequence of 1's and zero magnetism for a sequence of 0's,
instead it receives a strong alternating magnetic field
and the 0's and 1' do NOT apply amplitude modulation,
but frequency or phase encoding, or something more esoteric.

If as you appear to suspect, a sequence of 0's was a sequence of nothings, then the data would NOT be self-clocking,
and then 1000 0's between a pair of 1's would become either 999 or 1001 given an error of 0.1% in the accuracy of time measurement or speed of rotation.

#5 OFFLINE Augeas

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Posted 18 March 2011 - 05:20 PM

A little more clarity to my first post:

The Options/Settings/Wipe Free Space option uses one pass of binary zeroes (as does Secure Deletion of files one pass).

The Drive Wiper gives a choice of overwrite patterns, from one to 35 passes. I would assume that the one pass is binary zeroes. In the Gutmann 35-pass overwrite there are a series of different overwrite patterns, of which one is binary zeroes. The end result of a 35-pass overwrite with CC is zeroes, although this is pass number 10 (I think) in the obsolete Gutmann process.

Alan is of course correct, no data has ever been written directly to a disk, even in Gutmann's days. It is nowdays encoded many times so even if you could read the pattern on a disk it would be unintelligible. Actually bits aren't written to disk either, and a + doesn't indicate either a 1 or a 0 value, but that's another universe. What you see is what the disk controller has decoded and sent back to the O/S.

#6 OFFLINE Smoke86

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Posted 19 March 2011 - 07:02 AM

If I use the wipe will it take out all of the windows program aswell or no

#7 OFFLINE Nergal

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Posted 23 March 2011 - 10:53 PM

If I use the wipe will it take out all of the windows program aswell or no

Freespace wipe: will not
Full wipe: You cannot full wipe your system drive so unless your program files are on a second drive, then no.

Next time please open your own thread though. I know that this one has an ambiguous title
ADVICE FOR USING CCleaner'S REGISTRY INTEGRITY SECTION
DON'T JUST CLEAN EVERYTHING THAT'S CHECKED OFF.
Do your Registry Cleaning in small bits (at the very least Check-mark by Check-mark)
ALWAYS BACKUP THE ENTRY, YOU NEVER KNOW WHAT YOU'LL BREAK IF YOU DON'T.
CCLEANER, RECUVA, DEFRAGGLER AND SPECCY DOCUMENTATION CAN BE FOUND AT www.piriform.com/docs
Link to Winapp2.ini explanation