When we delete files permanently from PC they are still there in PC. But if we install Windows are the deleted stuffs still there in PC?
As far as a newly installed or re-installed O/S is concerned, all the space not taken up by the O/S is empty and free to be used. The only files the O/S "knows" about are the ones created during the install.
there can be left over files not seen by the OS if the format is quick
I think one can look at this in a variety of different ways. When you delete files in Windows (whether by putting them in the bin and emptying it or otherwise), the files are marked as deleted. The files themselves are not normally overwritten but the space is marked as free, so they don't "use up space".
From this point on, it's a matter of luck. If you write another file onto disc, and it happens to be written onto the space occupied by the deleted files, then they are truly erased. Otherwise, they are still there and it may be possible to recover the data with suitable tools.
So, from the point of view of recovering disc space, yes, the files don't claim any space on the disc. From a security standpoint, the data may still be there and it may be possible to recover it, and likewise from a data-recovery perspective.
If you want to ensure that it will not be possible to recover the data, you should "shred" the files or "wipe free space" on the disc with suitable software. There are plenty of programs that can do this, including CCLeaner and IOBit uninstaller. Wiping the free space means writing random data over any part of the drive that is not marked as in use, including your deleted files. Shredding allows you to overwrite the data of specific, named files. In either case, the result is that the wiped/shredded files are no more and the data cannot be recovered.
Please on my install ment massega
I always format my c drive before installing
If you've done a quick format then there can be possibility to recover deleted files. Darik’s Boot and Nuke (DBAN) wipes your hard drive by overwriting it with junk data, it will overwrite the entire hard drive, including recovery partitions
guys I first of all thnx for ur rply.And i want to know that when we delete the files permanently they r still present in pc means they occupies space in my pc somewhere but when i install windows r they still there or removed from pc.
The part 'they occupy space in my PC somewhere' is misleading. The space occupied by the files may not have been overwritten, but that space is marked as "available for use" so as far as the system is concerned, that space is NOT occupied. Like I stated above, depending on HOW Windows was reinstalled an if a tool such as DBAN was used prior to the reinstallation will determine as well as how you define "if the files are still there" will change the answer between the various potentials.
No matter how you define if old data is still there, if you use DBAN, it will be gone.
If you reformatted the drive, old data might still be recoverable using manual methods.
If you reinstalled without reformatting, there will be old data there that might be either manually or automatically recoverable.
5 Tools To Permanently Delete Sensitive Data From Your Hard Drive [Windows]
Why It Is Impossible To Recover Data From An Overwritten Hard Drive [Technology Explained]
Bruce just about summed it up but I would just like to add that if you're truly concerned about your data not being recovered, use DBAN Live CD to wipe your drive clean before a reformat. I still advice doing a full reformat afterwords though.
It depends. If Windows is installed/reinstalled without reformatting the drive, other data may still be recoverable. If it is done with a Quick Format, the MFT (Master File Table) is rewritten and truncated, so the file metadata will no longer exist and neither will any files small enough that they were stored in the MFT. Even without this metadata, files can still be recovered but it becomes a much more tedious manual process. Choosing to do a full format of the drive still does not overwrite all previously existing content. If you want to ensure that no pre-existing data survives the process, you are better off using DBAN (Darik's Boot and Nuke) to completely wipe the drive before installing Windows.