1. (tl;dr – skip to bottom for instructions, see also update post) The CID register on SD cards is supposed to be read-only, which means it can be used to lock devices to specific SD cards, preventing the user swapping them out, which is very annoying.
2. Internal SD Card Information Information about an SD card is encoded in its internal card registries. One of these is the Card Identification (CID) Register, a 16 byte code that contains information that uniquely identifies the SD card, including the card serial number (PSN), manufacturer ID number (MID) and manufacture date (MDT).

1. How To Change Cid On Sd Card
2. Sd Card Cid Reader
3. Sd Card Cid Register
4. Sd Card Cid Rewriter

Summary :

Secure Digital (SD) cards are used in plenty of consumer electronic devices. And users are allowed to encrypt their SD cards to prevent others from accessing the data, which is a great security solution. In this post, MiniTool introduces more detailed information about it as well as how to decrypt SD card.

Right click the SD card partition, and click “ Advanced ” and then “ Change Serial Number ”. In the pop-out window, you can edit a new serial number such as 123456. Go to My Computer, click Devices with Removable Storage right click SD card or USB drive and choose Properties choose to Remove write-protection. Option 3: Connect SD card or USB drive with PC, click Start. Type regedit in the search bar and click it.

About SD Card

SD card, introduced by SanDisk, Matsushita Electric and Toshiba, is a non-volatile memory card. It is designed for portable devices, such as digital cameras, camcorders, video game consoles and smartphones. These devices use SD card to store photos, videos, audio files, applications and other files.

It has been quite popular for the small and lightweight features since it was developed and marketed in 1999. Although you may benefit a lot from SD card, increasing risks are coming towards you, too. So, you had better take some precautions to protect your data. Here are some easy ways you can take into consideration according to your needs:

1. Avoid Physical Damages: the small SD card is susceptible to physical damages and you need to keep it away from water, fire and any heavy stuff whenever it is not in use. Once it’s physically broken, the data in your SD card will be unable to be recovered by most data recovery applications.
2. Keep your SD card in a secure location: besides avoiding physical damages, you should also keep it in a secure location (like a locked cabinet or a safe) to prevent your SD card from being stolen if there is any personal or precious data in it.
3. Write-protect data: if your SD card is write-protected, the data in it will be unable to be changed or deleted by anyone, including yourself. You can do it by pushing the switch at the left side of the card to the lock position. To remove the write protection, you can push the switch back or find solutions in this post.
4. Encrypt SD card: another simple way to protect your data from wrong hands is to encrypt SD card. In this way, your SD card will be unable to read without authorized access. You can get the detailed steps in the following part.

How to Encrypt SD Card

When you want to stop others from accessing your SD card and checking the files on it, you can encrypt SD card, which adds an extra layer of security.

In this way, the data on your SD card will be locked to your device. Only people who have the password can read and modify the data. If the card is removed, lost or stolen, the information won’t be read even if it’s installed on another device.

Before the operation, here are some rules you should know:

1. Make sure that there is enough power on your device.
2. You cannot access the encrypted SD card on another device even if you have the password. You need to pay attention that if you lose the original device where you encrypt SD card, you will lose the access to the files forever.
3. If your device used to encrypt the SD card is reset to factory default settings, it will be impossible to read the encrypted SD card anymore.
4. You cannot use the card during the encryption process.
5. To access the files in the encrypted SD card, you can unlock it with the password or decrypt SD card.

Now, let’s see how to encrypt SD card.

Encrypt SD Card on Android

You can encrypt SD card through mobile phone, and your Android driver should have the feature for encryption. I’d like to take a Samsung device as an example.

Step 1: Go to Settings and tap Lock screen and Security.

Step 2: Find the option Encrypt SD card and select it.

Step 3: Press Encrypt SD card button and enter your password, PIN or pattern to continue.

Then the device will begin the encryption. During the process, you’re free to use your device and the encryption process will show in the notification panel. If there is a lot of data in your SD card, it may take a long time. Please wait patiently until it’s finished.

Encrypt SD Card on Windows 10

If you have an SD card reader, you can also connect the SD card to computer with it and encrypt SD card on computer. Here is the guide on how to encrypt SD card on Windows 10, and you can have a try.

Step 1: Connect your SD card to Windows 10.

Step 2: Press Win + E to open File Explorer. Then click This PC on the left pane.

Step 3: Under Devices and drives, right-click your SD card (USB Drive) and select Turn on BitLocker. Then BitLocker will take some time to initialize the drive and you just need to wait until the next window appears.

Step 4: Choose how you want to unlock this drive and click Next to continue the process. Here are two options listed below. In this case, I choose the first one.

• Use a password to unlock the drive: the password should be over 8 characters and contain uppercase and lowercase letters, numbers, spaces and symbols. Besides, you have to reenter your password to confirm it.
• Use my smart card to unlock the drive: if you choose this option, you will need to insert your smart card, and the smart card PIN will be required when you unlock the drive.

Step 5: In the pop-up window, choose a way to back up your recovery key. If you forget your password or lose your smart card, you can use the recovery key to access your drive. Here I choose Save to a file.

Step 6: When your recovery key has been saved, click Next. Then choose Encrypt used disk space only (faster and best for the new PCs and drives) or Encrypt entire drive (slower but best for PCs and drives already in use). Click Next.

Step 7: Select Compatible mode and click Next. Then choose Start encrypting. The encryption might take a while depending on the size of your SD card. After it is 100% completed, click Close and restart your computer to save the changes.

Once the computer restarts, you will find that your SD card is locked and you need to enter the password if you want to check files. If you don’t need the encryption anymore, you can decrypt SD card. There is a step-by-step tutorial on how to remove the SD card lock in the following contents.

How to Decrypt SD Card

To decrypt an encrypted SD card, here are different ways you can take in different situations.

If you’re using the mobile device and you have the password, you can decrypt SD card on the same device easily without data loss.

If you have lost the password or you are unable to use the mobile device, you can decrypt it on computer. In this way, all the data in the SD card will be erased but you can use the decrypted SD card as a new storage device.

More detailed information is listed below, and you can choose one method according to your situation.

How to Decrypt SD Card with Password on Android

For SD card encrypted on Android device, you can decrypt it on the same device. It is easy to operate and you just need to:

1. Go to Settings > Lock screen and security > Decrypt SD card.
2. Input the password, PIN or pattern.
3. Wait patiently during the decryption process. Keep your device charged and you can check the progress in notification panel.

How to Decrypt SD Card on Windows 10 via Command Prompt

If you forget the password or lose your smart card and the recovery key doesn’t work, you can try decrypting the SD card with Command Prompt on Windows 10.

It may be a little risky if you are not familiar with this utility, because you might bring damage to your computer or other drivers in your computer if you type some commands wrongly. So, please be careful when you follow the steps below. Alternatively, you can try the next method which is simpler and securer.

Step 1: Connect your SD card to the computer.

Step 2: Press Win + R to invoke Run window. Then type cmd in the box and click OK to open Command Prompt.

Step 3: In Command Prompt, input diskpart and press Enter. Then type the following commands one by one and remember to press Enter after each to execute them.

• List disk
• Select disk * (* refers to the disk number of your encrypted SD card)
• Clean

Step 4: Wait until the process is finished. Then execute create partition primary and format fs=fat32 commands.

Then exit Command Prompt and your SD card will be decrypted successfully.

How to Decrypt SD Card on Windows 10 via MiniTool Partition Wizard

Another way to decrypt SD card on Windows 10 is to use MiniTool Partition Wizard, a wonderful partition manager and assistant. This is an alternative way of using Command Prompt, and it is easier to operate. You can achieve the goal within a few clicks. Besides, with this tool, you can even decrypt SD card after factory reset your mobile device.

Let’s see more details.

Step 1: Download and install MiniTool Partition Wizard by clicking the following button.

Step 2: Connect your encrypted SD card to Windows 10 and launch MiniTool Partition Wizard.

Step 3: Right-click your SD card and select Wipe Disk.

Step 4: Select a wiping method and click OK.

Step 5: Click Apply to execute the pending operations.

Step 6: Right-click the unallocated part of your SD card and click Create to create a new partition so that you can use this card to store new data.

Step 7: Specify the File System, Drive Letter, Size And Location and other information for the new partition. Then click OK to confirm the changes.

Step 8: Click Apply and then Yes.

Now your encrypted SD card is unlocked and you can use it as a new storage device.

Bottom Line

This post introduces some effective ways to protect the data in SD card, such as putting it at a safe place, write-protecting it and encrypting it, as well as the guide on how to decrypt SD card. Now, it’s your turn to have a try.

If you have any better ideas, please leave a message in the following comment section. And for any questions about MiniTool Partition Wizard, please don’t hesitate to contact us via [email protected].

How to Decrypt SD Card FAQ

Internal SD Card Information

Information about an SD card is encoded in its internal card registries. One of these is the Card Identification (CID) Register, a 16 byte code that contains information that uniquely identifies the SD card, including the card serial number (PSN), manufacturer ID number (MID) and manufacture date (MDT). The CID register is set when the card is manufactured and cannot be changed after it is set. (According to SD card specification the information is only to be written once, however if a card does not conform to the specification this information could be changed!)

How to read the CID from an SD card

One way to read the CID is to use a laptop with an SD card slot. Card readers in laptops are usually connected directly through the PCI bus (or IDE bus). This will not work through a USB card reader because the command to retrieve the card information is intercepted and not understood by card readers. Not all computers with built-in card slots will work, some internal card readers are connected through a USB bus.

How To Change Cid On Sd Card

Assuming you have the proper hardware, there are several methods you can use to get the card information. With Linux, reading the internal SD card information is simple. Insert the card and look under /sys/block/mmcblk0/device/ (this location may change depending on your platform, it may be mmcblk1 or in a different location). Under this location you will see several attributes available that include the CID and CSD registers and the information inside it.

To view the CID, the command is cat /sys/block/mmcblk0/device/cid (the exact location may be different)

What information is in the CID?

The following information is stored in the CID:

* these are the attribute titles used for the card in Linux

Sd Card Cid Reader

For more information, refer to the SD Association Simplified Specifications.

List of Common Manufacturer ID (MID)

Manufacturer ID (MID) are assigned by the SD Assoication (SD-3C LLC). They consider this information confidential so an official list is not published.

The following list was compiled by reading the CID on numerous SD cards. Many card brands are produced by OEM suppliers, and the MID and OEMID may reflect this, or in some cases they appear to show the producer of the card controller. For example, PNY cards have been found with 0x000028 and BE (Lexar) or 0x000027 and PH (Phison).

Sd Card Cid Register

Sd Card Cid Rewriter

How can I use the information from the CID?

The CID information can be helpful in identifying counterfeit memory cards. We include the CID data in our SD card reviews so you may compare it with your cards.