Deleted file protection

[tcleaner]

I have been using CCleaner on a laptop that was recently stolen. How hard is to recover files on that laptop that I have deleted and then run CCleaner? Is there a more permanent way (short of the impractical solution of constantly reformatting the harddrive) to delete files to protect myself in the future?

[Glenn]

Use Eraser

[rridgely]

Wow that sucks. I would be so angry if my laptop were stolen.

You could use eraser but I think the easier solution would just be to turn on secure shredding in CCleaner.

 

The person who stole it probably isn't smart enough to get your files back anyway.

[Tarq57]

I believe that if you delete the file using the OS, then run CCleaner, the previously deleted file will not be changed at all, ie it will still be recoverable. The more secure way would be to erase it using the seven pass erase method in CCleaner, or use eraser for the same job, using 3, 7, or 35 pass overwrite. Just deleting them won't destroy the file..just the header.

Once a file has been deleted (rather than erased) the only way to permanently remove it is to overwrite the space it occupied 3, 7 or more times. Eraser can do this. (Wipe free space)

[Glenn]

Another problem is that if you work with a file over a period of time, e.g., edit a long document using a word processor, you write multiple copies of the file to disk as you work. A file shredder only overwrites the last sectors to which the file was saved. To ensure that all the interim versions are unrecoverable, you have to use a freespace wiper.

[tcleaner]

Thanks for all the advice. How do I turn on secure shredding in CCleaner - is it a default setting? Unless secure shredding was a default setting, then I guess unfortunately I should assume my "deleted" files on the stolen laptop will be easily recoverable by the thieves.

[Tarq57]

It's not the default, (from memory), open CCleaner, click "options", click "settings" (top), and near the bottom of that window are the secure deletion options. 1, 3, or 7., or the (I think) default option, "normal file deletion(faster)"

 

So, yes, it would be safe to assume a lot of your data on that laptop would be recoverable by someone who knew enough to do it, and it isn't hard to learn a basic level of doing that. There are freeware programs that can do it. Some of the stuff would have been overwritten just with normal use, and that would be harder, or almost impossible to recover.

Sri.

[Pfipps]

Even overwriting once makes any form of software recovery impossible. So for practical purposes, a free space wipe with one overwrite

is enough. For the extra paranoid, 3 will do. Unless you have highly confidential data that someone will stop at nothing to get, you can

go to 7 for free space writing - incredibly slow. For sensitive files (Not free-space), I overwrite 7 times with Eraser because I can and it is still fast.

 

Even though this is an after the fact response, I recommend using Truecrypt for sensitive files on the computer, and monthly

free-space wipes. If the computer is stolen, the free space is muck and the encrypted files are as good as wiped.

 

Iolo offers a commercial free space wipe program that will search for previously deleted files (like recuva) and only overwrite those clusters.

However, I heard that Recuva will off that feature soon.