Recovering deleted files from a pen drive (Part 2 of 2, K2 #50)

Question of the Week
Is there any way to get back our files which we deleted from a pen drive?
— Rinzin

Answer (Part 2 of 2)
Dear Rinzin,

In the last column, I explained how to recover files that were accidentally deleted from a pen drive. Undeleting is possible because when you delete a file, it is only marked as deleted, but the content is still there. This is true for operational as well as failed devices. For this reason, a hacker can often recover data from a discarded pen drive or hard disk! To make sure no one can ever access your confidential files, the data must be securely overwritten (or the media physically destroyed). Organizations, such as governments, businesses, and ISPs, typically have special procedures for discarding hard disks and pen drives in order to safeguard their data and make sure the data do not fall into unwanted hands. Of course, individuals often also need to protect their digital information by securely deleting files.

How can you securely delete a file? Last week we recommended using a utility for recovering deleted files (Recuva, downloadable at goo.gl/O5f1W). This same utility can also overwrite deleted files. Once you overwrite a deleted file, it will be extremely difficult for a hacker to recover it. Overwriting is easy: After launching Recuva, search for the deleted files as you did in the case of undeleting. However, instead of undeleting, check the files you want to overwrite, then right-click and choose “Secure Overwrite Checked”. This will overwrite the checked files. These files are now gone forever, and it will no longer be possible to recover them.

If you need a more advanced tool, Eraser is the utility for you. Downloadable at goo.gl/aeidX, Eraser has many options to securely delete files, directories, the Recycle Bin and any unused space on a hard drive. It even has a scheduler, so the overwriting can occur when you’re out for a lunch break.

Bored with your generic pen drive? The Magic Mushroom is the gadget for you: Studded with diamonds, rubies and sapphires (as well as 32GB of storage, in case you’re concerned about that), this is the most expensive pen drive in the world: a bank loan of Nu 20 lakhs is all you need. Just remember to securely erase confidential files on the Magic Mushroom - it will help you sleep calmly if you ever lose it...

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Readers are encouraged to submit technology-related questions to boaz@thimphutech.com

Recovering delete files from a pen drive (Part 1 of 2, K2 #49)

Question of the Week
Is there any way to get back our files which we deleted from a pen drive?
— Rinzin

Answer (Part 1 of 2)
Dear Rinzin,

It could have been nice if files that are deleted from a pen drive would magically shift to the Recycle Bin, wouldn’t it? Still, never lose hope: It is often possible to recover deleted files from pen drives (as well as external hard drives and memory cards). When you delete a file, it is marked as deleted, but its contents are not immediately erased. As long as the data is not overwritten, there is a good chance that the file can be undeleted. So first, make sure not to create any new files or edit existing ones in this pen drive. By not tampering with files on the pen drive, you increase the chances of recovery.

Next, we will need a utility that scans the drive, looks for deleted files, and then salvages your treasures. One such utility is Recuva, a small but powerful program: In addition to undeleting files from your pen drive, Recuva can also try to recover files that were deleted from the Recycle Bin! First, download Recuva at goo.gl/O5f1W. After installing, run the program and follow the prompts. You will be asked which types of files you wish to recover (pictures, music, documents, all files), and from where. Choose “Media card” for your pen drive. Recuva will scan the pen drive and find your files, which you can then magically retrieve by clicking the Recover button. Recuva is a snap to use.

The ease of undeleting files, by the way, also means that if you hand over a pen drive (or hard drive) to your friend, then if she is curious (and computer savvy), she can easily find information on that drive that you thought she’ll never see. How to deal with that situation? That will be the topic of our next column.

Reduce screen time

Does your child spend hours in front of the TV, computer, iPhone, or PlayStation? There is mounting evidence that excessive screen time is linked to various health and development problems, from obesity to attention deficit disorders. American teenagers spend around 8 hours daily in front various screens, and their urban Bhutanese peers are probably not too far behind. Experts recommend limiting exposure to ½ to 2 hours daily according to age, but not for babies: While it's tempting to use the TV or an iPhone as a babysitter, the American Academy of Pediatrics advises zero screen time before the age of 3.

Age	Daily Screen Hours
0-2	0
3-6	½
7-11	1
12-15	1 ½
16+	2

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Readers are encouraged to submit technology-related questions to boaz@thimphutech.com

2GB + Chillies = 1GB!

These chillies, they are not good for your brain. That's why we Bhutanese people haven't made much progress! If you have a 2GB memory, you'll go right down to 1GB with all these chillies."

— Tenzin Norbu, Thimphu

Four ways to share files - without getting infected

In a interesting recent PaSsu Diary post, Passang Tshering wrote about his USB flash-drive being infected by a rather nasty virus after inserting the drive into a student’s laptop. Since so many laptops and desktops in Bhutan are infected with viruses, exchanging flash-drives is extremely risky. In fact, this is the most common way by which viruses are spread.

Here are four ways which enable file exchange with a very low risk of infection. They might need a bit more work that just swapping the flash-drive, but they will save your laptop.