FAQ (frequently-asked questions)

Questions regarding the need for data erasure, “Disk Shredder 7” operation, and conditions of use are summarized below.

FAQs on the need for Disk Shredder 7 (data erasure) CONTENTS.
Q.1 Why can't I just put a file in the Windows “Recycle Bin” and choose “Empty Recycle Bin” to completely erase it? Q.2 Can't I just format the hard drive to completely erase it? Q.3 Can't I just reinstall the OS and pre-installed software from the recovery CD-ROM to completely erase it? Q.4 In the case of leased or rented items, wouldn't a data-erasure service from a vendor be sufficient? Q.5 What is the best use for the Disk Shredder 7? Q.6 Why write random numbers? Is it not enough to write 0 (zero)? Q.7 How can I reuse a hard disk after using “Disk Shredder 7”? Q.8 You say that Disk Shredder 7 “completely erases” the contents of a hard disk. What exactly does that mean? In particular, what happens if the hard disk has a hardware defect that prevents it from being written to by software?
FAQs on the operation of Disk Shredder 7 CONTENTS.
Q.9 In what form does Disk Shredder 7 run? Does it install to a hard disk? Q.10 What is the best way to use the software when there are many computers whose data you want to erase? Q.11 Disk Shredder 7 recommends the use of the USB flash drive version, but is there any danger that the program written to the USB flash drive could be rewritten if the computer is infected by a virus or other malware? Q.12 I would like to purchase multiple copies of Disk Shredder 7 for simultaneous use and backup purposes.
FAQs on Disk Shredder 7 Software License Agreement CONTENTS.
Q.13 Is it possible to make a backup of a USB flash drive or DVD-ROM before running “Disk Shredder 7”? Q.14 If we continue to use “Disk Shredder 7” after the second year, it would be a hassle to pay each time we request a replacement due to damage to the USB flash drive or DVD-ROM. Is there a maintenance contract system that allows us to pay a fixed annual fee to replace the USB flash drive or DVD-ROM at no additional cost during the term of the contract? Q.15 If I replace a damaged USB flash drive or DVD-ROM, can I use “Disk Shredder 7” during the replacement period? Q.16 What happens if there is a sector that cannot be written to by normal software due to a defective hard disk? Q.17 We are in the business of computer rental, and in a case where we want to use a rented computer to erase data, is it OK if we lend a USB flash drive or DVD-ROM of “Disk Shredder 7” together with the computer, and let the customer at the rental destination run “Disk Shredder 7”? Is this acceptable?

FAQs on the need for Disk Shredder 7 (data erasure)

Q.1 Why can't I just put a file in the Windows “Recycle Bin” and choose “Empty Recycle Bin” to completely erase it?
Hard disks are largely divided into “management area” and “data area. Comparing to a warehouse, the management area corresponds to the inventory of stored goods, and the data area corresponds to the storage area of goods. The management area contains only file information (file name, etc.) stored in the data area, while the actual file data is stored in the data area. The only operation to empty the recycle bin is to delete the relevant file information (equivalent to an inventory) from the management area. This leaves the file data itself (equivalent to an item) in the data area, so commercial file recovery software can be used to recover the management information from the data area and restore the file.
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Q.2 Can't I just format the hard drive to completely erase it?
The information that is erased by the formatting process depends on the OS and commands used. However, in Windows XP, for example, only the entire management area (see Q1) is erased in both “normal formatting” and “quick formatting”. The contents of the data area remain, so it is possible to recover files using commercially available file recovery software.
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Q.3 Can't I just reinstall the OS and pre-installed software from the recovery CD-ROM to completely erase it?
Reinstalling the OS or pre-installed software to an entire disk using a recovery CD-ROM will only overwrite a portion of the data area. In many cases, the previous data will remain intact.
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Q.4 In the case of leased or rented items, wouldn't a data-erasure service from a vendor be sufficient?
With the enforcement of the Personal Information Protection Law, companies are now legally required to manage personal information and prevent leaks.
It is true that the use of data-erasure services by vendors is part of information management enhancement. However, what the law requires is a thorough awareness of the need for companies to manage their own information, in other words, to have their own measures to protect themselves. Not leaving the protection of personal information to others is the first step.
When returning a PC due to lease expiration or rental termination, we recommend that you erase the data by yourself first.
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Q.5 What is the best use for the Disk Shredder 7?
Recycling/disposing of personal computers that contain confidential data or diverting them to other uses
It is important to completely erase unnecessary confidential data to prevent information leaks in the future, not only when recycling or disposing of the data, but even if the data is used for other purposes.
When returning a computer to the leasing/rental company at the end of the lease/rental period
Especially when returning equipment rented for a short period of time, such as for an exhibition, it is easy to forget to do so, but with Disk Shredder 7, complete erasure is easy.

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Q.6 Why write random numbers? Is it not enough to write 0 (zero)?
When writing data with a recognizable pattern, such as only 0s or 1s, it may be possible to guess the content of the original data from the residual magnetism if the data is read by a special device. For this reason, random number data is written to obscure the pattern, and then written over multiple times to make it difficult for special devices to read the original data. Thus, “Disk Shredder 7” is equipped with advanced functions to securely process PCs containing important confidential data.
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Q.7 How can I reuse a hard disk after using “Disk Shredder 7”?
You can reuse your hard disk by compartmentalizing, formatting, and performing a fresh install of the OS; the general procedure for Windows is to use a setup boot disk or recovery disk before starting the computer. Please refer to your computer's manual for specific instructions.
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Q.8 You say that Disk Shredder 7 “completely erases” the contents of a hard disk. What exactly does that mean? What exactly does that mean? In particular, what happens if the hard disk has a hardware defect that prevents it from being written to by software?
Disk Shredder 7” performs complete erasure by writing meaningless data to the entire disk area using standard commands (ATA commands) for hard disks. If there is a sector that cannot be written due to a defective hard disk, the erasure process will skip that sector and continue. At the end of the process, a message indicating that there was an error is displayed. The bad sectors are not overwritten by “Disk Shredder 7”. Other physical or chemical processing is required to erase the bad sector part.
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FAQs on the operation of Disk Shredder 7

Q.9 In what form does Disk Shredder 7 run? Does it install to a hard disk?
Disk Shredder 7 is software that is run from a USB flash drive or DVD-ROM. Installation on a hard disk is not required, but a USB flash drive must be connected to the target computer or a DVD-ROM must be placed in the drive until the data erasure process is completed.
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Q.10 What is the best way to use the software when there are many computers whose data you want to erase?
There is no limit to the number of times you can use the Disk Shredder 7 software, but only one computer can be processed at the same time per software (one USB flash drive or DVD-ROM). If you wish to process multiple computers at the same time, please purchase Disk Shredder 7 for the number of computers you need to process simultaneously. Incidentally, the processing time for data erasure depends largely on the performance of the hardware, the capacity of the hard disk drive (HDD), and the data erasure method, but it can take hours in the case of a large-capacity HDD. Please refer to “An Example of Erasure Time”.
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Q.11 Disk Shredder 7 recommends the use of the USB flash drive version, but is there any danger that the program written to the USB flash drive could be rewritten if the computer is infected by a virus or other malware?
The USB flash drive version of “Disk Shredder 7” is provided in a write-protected state. Therefore, even if your PC is infected with a virus, the virus will not affect the USB flash drive version of “Disk Shredder 7”.
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Q.12 I would like to purchase multiple copies of Disk Shredder 7 for simultaneous use and backup purposes.
Disk Shredder 7 is available in a 5-pack, which can erase up to 5 computers at the same time.
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FAQs on Disk Shredder 7 Software License Agreement

Q.13 Is it possible to make a backup of a USB flash drive or DVD-ROM before running “Disk Shredder 7”?
Duplication of the USB flash drive or DVD-ROM of “Disk Shredder 7”, including for backup purposes, is prohibited. However, to compensate for this, Personal Media Corporation (“PMC”) has established a system to replace damaged USB flash drive or DVD-ROMs with good ones. The replacement will be free of charge for one year from the date of purchase, after which it will be replaced for a fee.
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Q.14 If we continue to use “Disk Shredder 7” after the second year, it would be a hassle to pay each time we request a replacement due to damage to the USB flash drive or DVD-ROM. Is there a maintenance contract system that allows us to pay a fixed annual fee to replace the USB flash drive or DVD-ROM at no additional cost during the term of the contract?
If you require maintenance beyond that described in the “Disk Shredder 7” software terms of use, please contact us.
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Q.15 If I replace a damaged USB flash drive or DVD-ROM, can I use “Disk Shredder 7” during the replacement period?
PMC will send the replacement USB flash drive or DVD-ROM as soon as possible within PMC's normal business days, but please note that it will take about one week (about two weeks during major holidays and year-end and New Year holidays), including the time required for mailing and payment confirmation. PMC does not guarantee that the operation of the software will not be interrupted. If there is a possibility that you cannot wait for the replacement product to arrive, PMC recommends that you purchase multiple copies of Disk Shredder 7 to improve operational efficiency and for backup purposes as well.
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Q.16 What happens if there is a sector that cannot be written to by normal software due to a defective hard disk?
"Disk Shredder 7” skips such sectors and continues the erasure process, displaying a message at the end of the process indicating that there was an error. Please note that the original data in such sectors may not have been erased.
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Q.17 We are in the business of computer rental, and in a case where we want to use a rented computer to erase data, is it OK if we lend a USB flash drive or DVD-ROM of “Disk Shredder 7” together with the computer, and let the customer at the rental destination run “Disk Shredder 7”? Is this acceptable?
Since Article 2.3 of the “Disk Shredder 7” software terms of use clearly states “within the same office of the organization to which the customer belongs” and Article 3.3 also states that such use is not permitted without PMC's permission. However, we offer different license conditions and contract forms from the general package to take into account the circumstances of rental companies. Please feel free to contact us for more information.
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