Does reinstalling windows delete everything?

Biz.Kid09

Biz.Kid09

Biz.Kid09

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I have just sold a laptop and i re installed windows 2 times, But i was just wondering does that mean i have deleted everything? so nothing can ever be recovered?
It came withe win vista then i re installed vista, Then installed win 7 when it came out then i installed win 7 again before i sent it, I am assuming this ammount of installs would be fine but just wanted to make sure.
 
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sorry read the thread incorrectly.

Someone could try and get something out of it, but im sure you had nothing worth anything to anyone anyway, so why would you care?
 
I was just wondering, I have done some banking on it but not recently also ebay apart from that, Is it easy to get stuff? I have always wondered,
 
when i installed win7 over the top of vista it left parts of vista like program folders etc BUT that can be deleted.

i think what your asking is does reinstalling over the top wipe the cookies etc left from online banking and ebay etc.
my answer would yes as those cookies can be deleted when doing a disk cleanup, as reinstalling give you everything from fresh i dont think those cookies would still be there.

someone else like bleed and co could clarify this but this is just my penny's worth!
 
Yes, data will be recoverable, how far back will depend on how much usage you gave the disk. If it was 500gb and you only ever 'turned over' 100gb of file data in the duration of its life then a lot will be recoverable.

Testdisk for example can even try get a whole partition back.

Always secure erase your drives when you move them on, if you do not data WILL be recoverable. When you delete a file, you do not actually delete it. You just mark the area on the disk as usable. This is why (Quick) formats are near instantaneous and 'normal' ones take significantly longer.

I have recovered 3 year olds photos from SD cards. Give me that disk and I could conceivably recover, for example, Firefox's history file, extract it all out into a nice readable format and see your browsing habits.
 
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It's likely a lot of things are still there if you didn't format upon reinstall as windows will put most things in a folder called windows.old. So you will have a windows.old in a windows.old folder containing maybe program files and user data/files.

If you formatted each time you're probably ok as the disc areas will have been overwritten a few times making it tricky (though not impossible) to recover your old data.

(That's not to say formatting overwrites the data, but when you reinstall on a formatted disc the install will go to the beginning of the disc therefore overwriting your previous OS location)
 
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Sin_Chase said:
Always secure erase your drives when you move them on, if you do not data WILL be recoverable. When you delete a file, you do not actually delete it. You just mark the area on the disk as usable. This is why (Quick) formats are near instantaneous and 'normal' ones take significantly longer.
Click to expand...

Afaik normal formats are longer because it runs scan disk before formatting, nothing to do with making things less recoverable.

Edit - http://support.microsoft.com/kb/302686
 
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Hmm indeed.

Anyway the point was to illustrate that Windows installation Quick formats are so quick because they only mark space as usable instead of re-writing random or blocks of identical data to the sectors and that it's never really "gone" until you do this...or chuck it on a degausser :D
 
Whether you've reinstalled Windows isn't particularly relevant, because there are lots of ways you could reinstall Windows, and make it more or less difficult for someone to get data back. You can install Windows without formatting the drive, in which case the data will be intact. You can install Windows and do a quick format, in which case the data would appear to be gone but still exists until it's overwritten. You can install Windows and do a standard format, in which case the data is much harder (but still not impossible) to retrieve. If you wanted to be absolutely sure that your data was inaccessible, even that wouldn't be sufficient.

It all depends on how important your data is and how determined someone is to get it back. If it's online banking passwords, which aren't generally saved anyway, you don't really have much to worry about.
 
All this talk makes me want to attempt to recover a partition, write it to disk and try boot the system on it, bust the password (if any) and see if any saved sessions via cookies are persistent :D
 
well i stand totally corrected!
remind me to never to give you guys any of my hdds or flash memory you wont find naked pics of gf:p
 
bennyB said:
Yeah it is easy if it's just been deleted, my point is that it is likely it will have been physically overwritten which has been shown to be "tricky" to recover even after one overwrite: "Special Publication 800-88: Guidelines for Media Sanitization" (PDF). NIST. September 2006.
Click to expand...

Likely depends on what and when.

You have to remember the whole process is perpetual, so for every sector that gets overwritten thats also a fresh piece of data that could be recovered from a delete/format until that sector gets over-written again!

Stuff from the early life of the disk? Unlikely perhaps yes. Stuff written the day before selling it? Likely! :D
 
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