How do I *completely* kill all files when re-installing

[shiphen]

Hi
How do I *completely* kill all files when re-installing Window7 Pro (64bit)?

BACKGROUND
The problem I have is that my previous installation of Windows7 picked up some trojans/viruses and I want to make double sure that there is nothing left on my disk.

I have tried booting from the Windows7 DVD, but it only does a very unconvincing format that appears to take about 3 seconds.

Cheers


Ship

 

[Pauly]

Download a free program like killdisk and format the HDD with this and it will return the drive to all zeros or all ones totally blanking anything on there although it will take a little while especially if its a big disk ie 1TB, once downloaded it will give you the option to create a boot disk, make it, boot from it, then blank the HDD and your ready to install

Hope this helps

 

[shiphen]

Yes, I tried downloading an ISO file from killdisk.com, which I burnt to CD and then booted my Windows7PC from it. But I found it confusing. I did get it to delete some files (I think) but it didnt take more about 20 seconds... I was also slightly alarmed that it didnt talk about Windows7 anywhere but maybe that doesnt matter!

Roughly how long would you expect it to take to completely blank a 500GB disk?
Minutes? hours? days?

 

[Pauly]

It depends on the settings you choose but normal full format maybe 1-2 hours but that is a guess theres lots of things that can affect it, system type/speed, HDD type, program settings etc

 

[ignatzatsonic]

Who made your hard drive?

The drive utilities at the manufacturer's web site nearly always include a method to write zeros to the entire drive, as you might do before disposing of it. I used it recently on a Western Digital drive.

You don't need to burn a disc.

I am guessing these apps will work when you have a one drive system. It may be that you have to connect the drive to another working system, but I doubt it. I've always had an OS drive available.

Pauly is correct about required time.

 

[shiphen]

Thanks - but no one has answered my question about can viruses get through a re-installation of Windows7?

 

[ignatzatsonic]

You can find conflicting info on this on the web.

Most of the sources I looked at say "writing zeroes" gets all sectors including boot sector, MBR, etc.

Many sources even say deleting all partitions and a full format is enough.

But if you are in full paranoia mode, and many are, you should probably drill holes in the drive, beat it with a sledgehammer, and discard it. You can always find someone to tell you that you didn't do enough.

 

[Shinobi73]

Thanks - but no one has answered my question about can viruses get through a re-installation of Windows7?

I'd have to go with just clearing partitions and the full format... it's always worked for me :huh:

 

[shiphen]

Thanks - but no one has answered my question about can viruses get through a re-installation of Windows7?

I'd have to go with just clearing partitions and the full format... it's always worked for me :huh:

When you guys talk about "full format", what do you mean?

I tried running KillDisk but couldnt really understand it - I ran something that took suspiciously little time (about 20 seconds) on my 0.5TB disk. Probably not a "FULL format"??

Either way I ran out of time and reinstalled Window7. During the process I asked it to delete all the partitions, and I resized them. For some reason there is now a partition (100GB) that I cant even SEE - that Windows seemed to want to create for its own internal use. I am worried that because Windows7 came with the hard disk that it has been lazy and has NOT deleted everything on the disk - even though I can't actually see any of my previous files on the new installation. But remember I cant see that 100GB partition either!

My gut feel is that I have NOT done a full format, and that I could still be vulnerable to lurking viruses.

- Any further thoughts?

 

[theog]

Use method two (command prompt at boot) in this tutorial:

http://www.sevenforums.com/tutorials/2668-partition-volume-delete.html

Have look at those:

http://www.sevenforums.com/installa...ck-reference-list-installing-windows-7-a.html

http://www.sevenforums.com/installation-setup/34853-common-installation-problems.html

http://www.sevenforums.com/tutorials/1649-clean-install-windows-7-a.html?ltr=C

 

[ignatzatsonic]

Two ideas:

Run the write zeroes application within your drive manufacturer's disk utility as I mentioned earlier in this thread.

If you don't want to write zeroes, but do want to get rid of that 100 MB hidden system reserved partition and do a full format, you can reinstall Windows 7 in this manner:

1. Once Windows 7 Setup is loaded, press Shift + F10 keys at the first setup screen (which allows selection of language, keyboard and locale). A Command Prompt window will be opened.

2. Run Diskpart, the built-in disk partitioning tool of Windows 7 with the following command:

diskpart

3. Type in the following commands one by one, followed by the Enter key; (text in parentheses are comments only):

list disk (to show the ID numbers of the hard disks available, in a one disk system you should see only Disk 0)

select disk 0 (change 0 to another number if installing on some other disk)

clean (this deletes all partitions on the selected disk)

create partition primary (creates one new partition covering the entire selected disk; create others later in Windows if needed)

select partition 1 (chooses the partition you just made)

active (makes that partition active)

format fs=ntfs (full formats the partition)

exit (dumps you back into the Windows 7 install where you continue as usual)

 

[shiphen]

Thanks, ignatzatsonic
But b*gger, I fear it is now too late, because I have installed Window7 on my disk, (and I would now lose about 5 hours work to revert!)

FWIW, I did try shift/F10 but couldnt get it to work, perhaps because I was trying to do so at the "where do you want windows installed?" screeen rather than earlier. (sigh - they dont make this easy, do they?)

But no one seems to be answering my central question: Is it possible/likely that a virus could survive a full reinstallation of Window7 including resizing of the partitions on the disk (but not including a format as such)?

Ship

 

[Pauly]

i very much doubt anything would survive, i only ever format with win and always been ok

Once you have finished installing, get windows updated and your core programs installed and working and then consider taking a system image with backup and restore in control panel, this will take an image of your HDD and in the event of damage to OS or future HDD failure you can reimage the system back to your drive and return to the point in time you made the backup making reinstalls a thing of the past

 

[Shinobi73]

I can't really say, personaly i've never encountered a virus to survive a full format of the HD before re-installation of the OS so if you performed the custom install and formated the HD first before installing the OS it should be OK.

 

[ignatzatsonic]

You are asking for certainty and there is none.

You are worried that you are already infected. If so, any image you make will contain the infection.

You have a simple decision tree:

Am I worried enough to warrant saying goodbye to my 5 hours of work and starting over by zeroing and repartitioning?

Yes or no.

Nothing anyone can tell you in this or other threads is going to get rid of your worries. After all, any advice you get COULD BE WRONG!!!!!

So you either live with it or start over.

But even if you start over and zero the drive, is that enough???

Repeat loop ad infinitum.

 

[surfasb]

Thanks - but no one has answered my question about can viruses get through a re-installation of Windows7?

Technically, no virus or trojan can get through a Custom Install of Windows 7. Boot viruses will be overwritten. All other viruses will be orphaned. The only way to get a virus or trojan from a previous installation is through your old data files.

Your best bet is to concentrate on disinfecting your data files, not worrying about your installation method of windows.

 

[shiphen]

You are asking for certainty and there is none.

You are worried that you are already infected. If so, any image you make will contain the infection.

You have a simple decision tree:

Am I worried enough to warrant saying goodbye to my 5 hours of work and starting over by zeroing and repartitioning?

Yes or no.

Nothing anyone can tell you in this or other threads is going to get rid of your worries. After all, any advice you get COULD BE WRONG!!!!!

So you either live with it or start over.

But even if you start over and zero the drive, is that enough???

Repeat loop ad infinitum.

I am no expert but I dont get the reason for this lack of certainty.
Surely it's down to physics!

Surely a virus can only exist as some sort of file, no?
And either ALL files on a disk will be deleted by a full Win7 reinstall or they may not be.
If there is any scenario whereby a full Win7 reinstall (involving resizing of partitions) does leave behind files, or there is not.

To recap, I am booting from the Win7 DVD, right?
So the hard disk shouldnt even be *TOUCHED* until windows asks it about its partition sizes. It there any conceivable way that a really nasty virus could leap up and stop itself from being deleted along with all other files on the disk?

OR is Windows lazy and does it NOT delete every file on disk (if they have certain rights...).

OR wait a minute, perhaps certain viruses are able to burrow through the file partitioning structure and lurk in structures outside of the file structure system and exist in some other format that are not really files as we know them... ??

 

[surfasb]

You are asking for certainty and there is none.

You are worried that you are already infected. If so, any image you make will contain the infection.

You have a simple decision tree:

Am I worried enough to warrant saying goodbye to my 5 hours of work and starting over by zeroing and repartitioning?

Yes or no.

Nothing anyone can tell you in this or other threads is going to get rid of your worries. After all, any advice you get COULD BE WRONG!!!!!

So you either live with it or start over.

But even if you start over and zero the drive, is that enough???

Repeat loop ad infinitum.

I am no expert but I dont get the reason for this lack of certainty.
Surely it's down to physics!

Surely a virus can only exist as some sort of file, no?
And either ALL files on a disk will be deleted by a full Win7 reinstall or they may not be.

Some viruses use to infect the MBR. Those are no longer effective.
For all practical purposes, if you wipe a partition, all virus and trojans that live on that partition are dead. If you don't wipe the partition, a full Win7 reinstall will orphan the viruses and trojans.

If there is any scenario whereby a full Win7 reinstall (involving resizing of partitions) does leave behind files, or there is not.

All Win7 reinstalls that don't wipe the partition will move the old Windows, ProgramFiles, ProgramData, and User folders to a folder called Windows.old. So ya, there could be viruses still there, but you would have to run those programs or files explicitly to reinfect your computer. Essentially they exist inside a box and only by opening the box(running the program) can you reinfect your system.

Didn't I just type all this in my previous posts?????

To recap, I am booting from the Win7 DVD, right?
So the hard disk shouldnt even be *TOUCHED* until windows asks it about its partition sizes. It there any conceivable way that a really nasty virus could leap up and stop itself from being deleted along with all other files on the disk?

Nope.

OR is Windows lazy and does it NOT delete every file on disk (if they have certain rights...).

OR wait a minute, perhaps certain viruses are able to burrow through the file partitioning structure and lurk in structures outside of the file structure system and exist in some other format that are not really files as we know them... ??

Nope.

 

[shiphen]

All Win7 reinstalls that don't wipe the partition will move the old Windows, ProgramFiles, ProgramData, and User folders to a folder called Windows.old.

Is there a way to erase the folder called Windows.old - and if so would that get rid of them?

(And does Windows.old house the Master Boot Record?)

I remain uneasy about orphaned things lurking on my hard disk. Some new virus might fire them up again no?

Ship

 

[surfasb]

All Win7 reinstalls that don't wipe the partition will move the old Windows, ProgramFiles, ProgramData, and User folders to a folder called Windows.old.

Is there a way to erase the folder called Windows.old - and if so would that get rid of them?

(And does Windows.old house the Master Boot Record?)

I remain uneasy about orphaned things lurking on my hard disk. Some new virus might fire them up again no?

Ship

Windows.old is just like any other folder. Highlight it and press delete. And no, it does not contain the MBR. You can't see the MBR from Explorer.

Technically a virus can reactivate orphaned virus, but that is about as likely as a plane falling out of the sky and hitting your house. One, the virus has spider its way through your harddrive to your Windows.old foler. Two, the virus has to be aware of how to reactivate these orphaned viruses.

I'm curious what files are you downloading that would load your system up with so many trojans and viruses.