Options/Settings Number of Overwrites bug in 3.12.1572

CCleaner for Windows CCleaner Windows Bug Reporting
1

I'm not sure if this is only in this version but thats somewhat irrelevant.

when "wipe free space" is selected in the main selection window and cleaner is run, it takes the same amount of time to clean regardless of the number of passes selected. i have a tiny 2.8gig partition [Temp (E:)] which houses my TIF and Cache and downloads etc, and i routinely wipe the free space with 3 passes. after updating it seemed considerably faster than previously so i decided to check it out.

it takes approx 46 seconds whether using "normal file deletion" or using "secure file deletion" with any number of passes from 1 to 35. it does, however, correctly quote the method in the post cleaning report. eg. "cleaning complete 46 seconds, Secure file deletion enabled - Very Complex Overwrite (35 passes)"

yet, if i wipe that partions free space thru the Tools/Drive Wiper route, then each increase in the number of overwrites significantly increases the clean time as it surely should, up to 1hr 15mins for 35 passes (estimated at the start and allowed to run for a couple of mins before cancelling).

therefore one would suspect from this that wiping free space thru the normal "run cleaner" operation is not wiping the free space as intended, and appears to be only using 1 pass regardless of settings, unless i'm missing something glaringly obvious, which wouldnt be a first time :s

2

I concur :) with your discovery of Advanced\Wipe Free Space bug.

On my OS partition with 63.4 GB free space a single pass ran 10:40 min/sec, a 3-pass ran 10:03 min/sec. Win7 64-bit.

My settings. setup1.pngcleanfrspce.png

3

thnx for your input kroozer.

ive now investigated further and the previous version does exactly the same. ive also more worrying findings on "secure" file deletion with the current version.

using a test file of 676MB which i repeatedly copied into a custom delete folder (with hindsight i could have copied into the TIF folder but the principle is the same) i ran the cleaner at various overwrite settings and got the following results which should speak for themselves (note i repeated each setting several times and reproduce here the most common result):

CLEANING COMPLETE - (0.777 secs)

------------------------------------------------------------------------------------------

676 MB removed.

Secure file deletion enabled - Very Complex Overwrite (35 passes)

CLEANING COMPLETE - (0.737 secs)

------------------------------------------------------------------------------------------

676 MB removed.

Secure file deletion enabled - Complex Overwrite (7 passes)

CLEANING COMPLETE - (0.738 secs)

------------------------------------------------------------------------------------------

676 MB removed.

Secure file deletion enabled - Advanced Overwrite (3 passes)

CLEANING COMPLETE - (0.799 secs)

------------------------------------------------------------------------------------------

676 MB removed.

Secure file deletion enabled - Simple Overwrite (1 pass)

CLEANING COMPLETE - (0.712 secs)

------------------------------------------------------------------------------------------

0 bytes removed.

Secure file deletion enabled - Very Complex Overwrite (35 passes)

according to this, the difference between overwriting zero bytes, and overwriting 676MB 35 times (which is actually writing 23,660MB isnt it?) is less than 0.1 secs. so it appears to me that everyone who believes theyre securely deleting their files with 3, 7 or even 35 passes, isnt. hopefully were getting 1 pass of random overwrites, which i guess is better than nothing. but my faith in ccleaner is totally shaken. previously if i had to take my pc in for repairs, i was confident that all my personal data was securely deleted.

id like to add here that i may be totally wrong in all my conclusions from these tests ive done. i'm no IT proffessional. and i apologise in advance if i am. but if i am wrong i'm sure i'm not the only one that would like it explained how these figures could mean anything else.

4

Good calls, kamak. Piriform will assuredly study your inquiry. :)

5

I remember a comment from a moderator that the number of passes applies to secure deletion of files,

and not the wiping of free space which is only a single pass.

6

You're spot on Alan, and that would apply to the first post. However post 3 seems to relate to secure file deletion.

On the few times I use secure file deletion I have found that it takes noticably longer to run with one pass (I never use more) and the file is indeed overwriten with zeroes. Kamak, could you look at the deleted files with Recuva, if you have it installed, and check that the file name has been changed to ZZZ's, and the contents - look at the header info in Recuva - have been changed to zeroes?

7

ok i installed Recuva, wiped the partitions free space with a program called Eraser to have a clean start and then used my test file as previously (copied it into a custom delete folder on that partition and ran ccleaner on 35 passes).

The file was no longer in the folder when looking for it normally.

Recuva recovered the file perfectly, its a movie and i could watch it.

so it seems that secure deletion isnt being applied to custom inclusions.

on a side note: perhaps a simple line of text at the "Wipe Free Space" settings - stating that its single pass only - would avoid any confusion in future on that matter.

8

. . . perhaps a simple line of text at the "Wipe Free Space" settings - stating that its single pass only - would avoid any confusion in future on that matter.

Like so? 1pass_only.png

9

on a side note: perhaps a simple line of text at the "Wipe Free Space" settings - stating that its single pass only - would avoid any confusion in future on that matter.

I definitely agree.

Software enhancements often have side effects that are discovered before shipping by running through a check-list of tests to run.

Sometimes the check-list is not adequate until the end-user suffers and complains.

QUESTIONS :-

Where and What is your drive E:\ ?

Primary / Secondary / External ?

Connection :- IDE / SATAn / USB ?

Format :- NTFS / FAT32 / ????

I guess there are 18 combinations and perhaps only 17 of them are on the pre-release check-list

10

as i stated in my opening post, drive E is simply a small partition. its on my main drive. i only have the one physical drive.

i'm pretty sure the connection is IDE, its just a standard, basic installation (if this is important and i need to check i'd need advice on how to)

and the file system is NTFS

11

I see nothing "special" that might be reasonable overlooked at pre-release.

12
so it seems that secure deletion isnt being applied to custom inclusions.

Does for me, so I guess it is specific to a certain combination of parameters or settings. I'll have a think on this.

Do you use the cleaner.ini file? What is your include setting for this folder? Is your drive a HD or SSD?

13

On the few times I use secure file deletion I have found that it takes noticably longer to run with one pass (I never use more) and the file is indeed overwriten with zeroes.

I suspect Piriform has rather quietly fixed/improved the secure file deletion since 3-pass no longer goes by the name DoD, and 7-pass no longer goes by the name NSA, and instead they use a more basic description. They also now take longer than 1-pass to complete like they should, whereas before I seriously doubt that anything above 1-pass worked at all.

As for Wipe Free Space doing 3-pass, 7-pass, etc., it has never did that! Those are for secure file deletion, not wiping free space. It's always only been a 1-pass for Wipe Free Space and it's easy to see how excellent that 1-pass is by using Recuva afterwords to verify if anything is left over.

14

Do you use the cleaner.ini file? What is your include setting for this folder? Is your drive a HD or SSD?

no i dont use cleaner.ini - setting is "E:\Downloads\*.*", include files and subfolders - i dont even know what "HD or SSD?" means.

As for Wipe Free Space doing 3-pass, 7-pass, etc., it has never did that!

Yeah we established that several days ago and have moved on, but i do want to say theres no need to say it as if only an idiot would even think it worked that way. If you wipe the free space through the "Tools - Drive Wiper" route then you get an option to choose the number of passes. So any normal person would assume that through the "Options - Settings" route the number of passes would also apply to free space. Even if that werent so, theres no reason to think that it doesnt work that way, and weve already discussed how a simple line of text in the window would prevent any confusion in the future and, as i said, weve moved on now.

15

Yeah we established that several days ago and have moved on, but i do want to say theres no need to say it as if only an idiot would even think it worked that way.

Originally I gave you remembered hearsay of the way things are.

Andavari has now provided additional information that this is not a recent defect but that it was always like this.

You have not till now been called an idiot.

What else can I call some one who does not like how a product works but chooses to be rude to the expert who has given new information.

If you wipe the free space through the "Tools - Drive Wiper" route then you get an option to choose the number of passes. So any normal person would assume that through the "Options - Settings" route the number of passes would also apply to free space.

Normal/Average people do not bother with Wiping Free Space.

Normal/Special people who have privacy concerns should not make rash assumptions.

A normal thinking person would not consider "Options - Settings" to be the route for Wiping Free Space,

but would recognise that at the bottom of the main Windows Tab is the Wipe Free Space check box to do the action,

and that will happen without ever using "Options - Settings"

weve already discussed how a simple line of text in the window would prevent any confusion in the future and, as i said, weve moved on now.

Fully agreed

16

When the deleted file is found using Recuva, do you do a normal scan to find it? Is it found under its proper name, i.e. not lots of ZZZ's? And the last modifed date - is it the date/time of the deletion?

HD is hard disk or drive, SSD is solid state device. I can't think of any easy way to tell which is which, off-hand, apart from the HD will make noises when reading or writing.

17

Speccy should indicate what sort of drive - it does for most systems anyway.

18

Originally I gave you remembered hearsay of the way things are.

Andavari has now provided additional information that this is not a recent defect but that it was always like this.

You have not till now been called an idiot.

What else can I call some one who does not like how a product works but chooses to be rude to the expert who has given new information.

It doesn't bother me if someone is rude on here, I don't take it personally since I simply won't offer them my volunteered help anymore. Rude people are the number one reason why I refuse to help as much as I did in the past!