Computer (with internal ) or fails to read 4GB, 8GB, 16GB, or 32GB SDHC card Why can't my (with internal card reader) read my 4GB or higher SDHC card? My digital camera can't read my 4GB SDHC card as well. What do I do?

SD and SDHC compliance If your computer's internal card reader works with 2GB (or lower) SD cards but fails to read a 4GB (or higher) SDHC card, then the computer's internal reader is not SDHC compliant. This same logic also applies to digital cameras, if the digital camera reads 2GB (or lower) SD cards but fails to read a 4GB (or higher) SDHC card, then the digital camera is not SDHC compliant.

SD and SDHC specifications The initial SD card specification defined the interface for cards only up to 2GB capacity. The subsequent SDHC specification was developed to provide increased capacity of 4GB – 32GB cards. and other products purchased before 2008 may not be SDHC compatible. Computers and other products purchased before 2007 are not SDHC compatible.

Verifying the card reader slot If the card reader slot on your computer does not have the SDHC logo, it is most likely not SDHC compatible and will only read cards up to 2GB capacity.

Other options you can use to read files on your SDHC card If your computer's card reader is not SDHC compatible, you have 3 options available:

1. You can connect your camera (or other device) that works with SDHC to your computer using a USB cable that came with the camera. You should be able to transfer files to the computer this way.

2. You can contact your computer manufacturer to see if they have a free update for your model that will make it SDHC compatible

3. You can buy inexpensive SanDisk SDHC card readers that will connect to your computer's USB port. SD/SDHC/SDXC is write protected or locked Why do I get a "The disk is write-protected" message when I transfer files to my SD card?

SOLUTION 1 - Unlock the memory card.

There is a Lock switch on the left side of the SD card. Make sure the Lock switch is slid up (unlock position). You will not be able to modify or delete the contents on the memory card if it is locked.

SOLUTION 2 - Toggle the lock switch.

If the lock switch is loose and moves easily It is likely the switch is sliding to the locked position as the card is placed in your host device. In this case the card will need to be replaced.

Please contact SanDisk support to check warranty status.

SD/SDHC/SDXC Specifications and Compatibility What SD (or microSD) cards are compatible with my host device? How do I choose the best card for my host device? There are three main types in the SD memory card family. SD, SD High Capacity (SDHC™), and SD Extended Capacity (SDXC™). This article details the different specifications of all three types of SD memory cards and the speed class ratings and compatibilities that are different with each type.

Click here to jump straight to Speed Class & UHS Speed Class Ratings Click here to jump straight to the Compatibility Summary

Additional Reference: SD Assocation Consumer Information

SD capacities range from 128MB to 2GB

Default Format: FAT16

SD cards will work in all host devices that support SD, SDHC, or SDXC

SD High Capacity (SDHC™) card is an SD™ memory card based on the SDA 2.0 specification.

SDHC capacities range from 4GB to 32GB

Default Format: FAT32

Because SDHC works differently than standard SD cards, this new format is NOT backwards compatible with host devices that only take SD (128MB - 2GB) cards. Most readers and host devices built after 2008 should be SDHC compatible.

To ensure compatibility, look for the SDHC logo on cards and host devices (cameras, , etc.)

SD Extended Capacity (SDXC™) card is an SD™ memory card based on the SDA 3.0 specification.

SDXC capacities range from 64GB to 2TB

Default Format: exFAT

Because SDXC uses a different file system called exFAT and it works differently than standard SD cards, this new format is NOT backwards compatible with host devices that only take SD (128MB to 2GB) or host devices that only take SDHC (4GB to 32GB). Most host devices built after 2010 should be SDXC compatible.

To ensure compatibility, look for the SDXC logo on cards and host devices (cameras, camcorders, etc.).

NOTE: Internal card readers on from 2008 and prior may NOT support SDXC cards. SDXC cards will work in SDHC compatible readers (not SD readers) if the computer OS supports exFAT. For more information on exFat see: Operating Systems that support the exFAT File System

Ultra High Speed, Phase I (UHS-I) bus design for SDHC and SDXC cards was added in SD spec 3.0. This is a design enhancement to increase the performance of SDHC/SDXC cards.

UHS-I specification defines two bus architecture options for up to 50MB/s (UHS-50) and 104MB/s (UHS-104) data transfer rates. These are theoretical maximum limits and actual maximum performance for a specific card is defined on it label or in advertising.

UHS is an enhancement to the original SD interface specifications. Host devices will obtain the UHS maximum speed when both the card and host device support UHS. Otherwise, the host device and card will use the slower SD maximum speed obtainable.

There is no compatibility problem using a UHS card with a non-UHS device.

Ultra High Speed Phase II (UHS-II) bus design for SDHC and SDXC was added in SD spec 4.0. This is an additional design enhacement with connector interface modifications to increase performance.

UHS-II specification defines bus architecture for options of 156MB/s and 312MB/s. Manufacturers implemented the 312MB/s option in memory cards. These are theoretical maximum limits and actual maximum performance for a specific card is defined on the label or in advertising. Host devices will obtain the maximum UHS-II speed when both the card and the host device support UHS-II. Otherwise, the host device and card will use the highest compatible UHS-I or SD bus speed.

There is no compatibility problem using a USH-II card in a UHS-I or non-UHS device.

Speed Class & UHS Speed Class Rating Speed class ratings define a minimum guaranteed speed of SDHC/SDXC cards. Speed class rating is important for HD video mode or camcorders, where the device is actually saving a steady stream of data. The resolution and format of the video determines the amount of steady stream data. You should consult your camera user manual for minimum speed class requirements for HD video modes.

Speed Class (SD Bus) Class Minimum Speed 2 2MB/s 4 4MB/s 6 6MB/s 8 8MB/s 10 10MB/s

UHS Speed Class (UHS Bus) UHS Class Minimum Speed 1 10MB/s 3 30MB/s

For a more detailed explanation of speed class see: Difference between Speed Class, UHS Speed Class, and Speed Ratings... SD Association: Speed Choices

Compatibility Summary The chart below shows the host device and the memory cards supported.

Host device Memory cards supported (ex. cameras, video recorders, phones, readers, etc.)

© images by sdcard.org

SDXC cards and host devices - SDXC memory cards can ONLY be used with SDXC host devices. - SDXC memory cards will NOT work with SD / SDHC host devices.

Additional info on SDXC cards and host devices - SDXC host devices can use and support SD, SDHC and SDXC memory cards. - SDHC host devices can use and support both SD and SDHC memory cards. - SDHC memory cards can be used with SDHC and SDXC host devices. Difference between Speed Class, UHS Speed Class, Speed Ratings (performance) and Video Speed Class for SD/SDHC/SDXC cards What is the difference between Speed Class and Speed Ratings for SDTM/SDHCTM cards? The speed rating measures maximum transfer speed for and writing images to and from a memory card, expressed as megabytes per second. However, video doesn't need as big a data pipe because the video format is a smaller "fixed stream" that uses only a portion of the data pipe.

Unlike card write speeds that measure maximum performance, class ratings measure the minimum sustained speed required for recording an even rate of video onto the card. The class rating number corresponds to the transfer rate measured in megabytes per second. Class 2 cards are designed for a minimum sustained transfer rate of 2 megabytes per second (MB/s)1, while Class 10 cards are designed for a minimum sustained transfer rate of 10MB/s2.

What does this difference mean for me?

Rated Speed (e.g. 15MB/s, 30MB/s, etc.) is maximum speed of the card and also what you would expect to approximately see in typical usage of writing or reading files on the card. This measurement is pertinent to still photography, especially for taking pictures with high resolution and/or saving in RAW format where the files created are very large. The faster the card, the faster it can save the file and be ready to take another picture. You can really notice speed differences with high-megapixel DSLR cameras when using multi-shot burst mode.

Still digital images shot on high-megapixel cameras should utilize fast data throughput (a large data pipe), higher speed cards for improved performance. Higher speed cards can also improve how fast you can transfer the files to and from the card and your computer.

Speed Class is a minimum speed based on a worst case scenario test. The Speed Class is important for video mode or camcorders, where the device is actually saving a steady stream of data. The resolution and format of the video determines the amount of steady stream data. This translates to a minimum speed you need to guarantee that the video captured on the cards is recorded at an even, sustained rate with no dropped frames (which would result in lost data and choppy playback).

Compared to high-megapixel photography, video doesn't need as big a data pipe because the video format is a smaller "fixed stream" that uses only a portion of the data pipe. But you do need a minimum guaranteed speed for the SDHC card that satisfies the requirement of the data stream. Your camera's specifications should state the minimum SDHC Class Rating required.

Using a card without the proper class rating on a more advanced camera, such as a high-definition (HD) or Digital Single Lens Reflex (DSLR) camera with HD video record settings is likely to result in an error message indicating that video can only be recorded at a lower definition setting.

The current SDHC specification defines Class 2, 4, 6, 8 and 10 as follows: Class Minimum Speed 2 2MB/s 4 4MB/s 6 6MB/s 8 8MB/s 10 10MB/s

UHS Speed Class was introduced in 2009 by the SD Association and is designed for SDHC and SDXC memory cards. UHS utilizes a new data bus that will not work in non-UHS host devices. If you use a UHS memory card in a non-UHS host, it will default to the standard data bus and use the "Speed Class" rating instead of the "UHS Speed Class" rating. UHS memory cards have a full higher potential of recording real time broadcasts, capturing large-size HD videos and extremely high quality professional HD. UHS Class Minimum Speed 1 10MB/s 3 30MB/s Video Speed Class or "V Class", was created by the SD Association to identify cards that can handle higher video resolutions and recording features. This speed class guarantees minimum sustained performance for recording video.

The other speed classes are either not optimized or are unable to accommodate the recording of multiple video streams, 360 capture, virtual reality content or 8K and higher resolution video. V Class Minimum Sustained Speed V6 6MB/s V10 10MB/s V30 30MB/s V60 60MB/s V90 90MB/s

1 1 megabyte (MB) = 1 million 2 Based on SanDisk internal testing; performance may vary depending upon host device. Data recovery for memory cards and flash drives How do I recover missing files or accidentally deleted files? What if my camera showed an error and all my pictures are missing? Also, can I recover my data if my memory card or flash drive stopped working? Can I 'undelete' files? How can I recover pictures from a memory card that has become unreadable?

SanDisk warranty does NOT provide reimbursement for data recovery services. This is specifically stated in our warranty. The SanDisk warranty covers the product itself, but does NOT cover any damages due to data loss. It is recommended to make regular backups of all your data and pictures.

Disclaimer Notice: Use of Third-Party Software or Websites

For functional memory cards and flash drives If your memory card or flash drive is still functional, you can try using a data recovery program. There is a high probability that your data can be recovered after you get an error while using the card, accidentally format it or delete files.

SanDisk recommends using RescuePro and RescuePro Deluxe. You can download a demo version of RescuePro and RescuePro Deluxe. These demo versions will show you what files can be recovered and provide a preview of the files for some common picture file types. The demo versions will require purchase of a license key to enable the feature to save the files. This is an excellent way to see if the program will work before you purchase.

RescuePro/RescuePro Deluxe for PC RescuePro/RescuePro Deluxe for Mac

After you recover your data, you can reformat your memory card or flash drive and use it again.

For Non-functional memory cards and flash drives If your memory card or flash drive is no longer functional or cannot be accessed by your computer, then you will need to send it to a data recovery company. They will attempt to recover data on your memory card or flash drive. SanDisk recommends LC Technologies for this. LC Technologies specializes in SanDisk products.

For customers in US, Canada and Europe, please refer to LC Technology Data Recovery for service description and current pricing. For customers in Asia and Japan, please refer to Kroll Ontrack or DriveSavers for service description and current pricing. Number of pictures that can be stored on a memory device How many pictures can my memory device hold? The following assumptions were made to calculate the number of images per card: MP = 1,000,000 pixels 1MB = 1,000,000 bytes, 1GB = 1,000MB TIFF image has 24 bit color depth, one of 16,777,216 colors per pixel JPEG 100% Quality = Visually lossless JPEG compression with 1:10 ratio of RAW image Photos - Compressed (JPEG 100% quality) Images per card.

NOTE: JPEG is the most common file format for consumer cameras.

Megapixels File size (MB) 1GB 2GB 4GB 8GB 16GB 32GB 64GB 128GB

4MP 1.2 715 1430 2861 5722 11444 22888 45776 91552

5MP 1.5 572 1144 2288 4577 9155 18310 36620 73240

6MP 1.8 476 953 1907 3814 7629 15258 30516 61032

7MP 2.1 408 817 1634 3269 6539 13078 26156 52312

8MP 2.4 357 715 1430 2861 5722 11444 22888 45776

10MP 3.0 286 572 1144 2288 4577 9155 18310 36620

12MP 3.6 238 476 953 1907 3814 7629 15258 30516

14MP 4.2 204 408 817 1634 3269 6539 13078 26156

16MP 4.8 178 357 715 1430 2861 5722 11444 22888

22MP 6.6 130 260 520 1040 2080 4161 8322 16644

Photos - Uncompressed RAW (24 bits per pixel) Images per card

Megapixels File size (MB) 1GB 2GB 4GB 8GB 16GB 32GB 64GB 128GB

4MP 12.0 71 143 286 572 1144 2288 4576 9152

5MP 15.0 57 114 228 457 915 1831 3662 7324

6MP 18.0 47 95 190 381 762 1525 3050 6100

7MP 21.0 40 81 163 326 653 1307 2614 5228

8MP 24.0 35 71 143 286 572 1144 2288 4576

10MP 30.0 28 57 114 228 457 915 1830 3660

12MP 36.0 23 47 95 190 381 762 1524 3048

14MP 42.0 20 40 81 163 326 653 1306 2612

16MP 48.0 17 35 71 143 286 572 1144 2288

22MP 66.0 13 26 52 104 208 416 832 1664 Formatting a memory card, flash drive or device using a PC How do I format my memory card, flash drive or device using a PC? NOTE: All SanDisk memory cards and flash drives come pre-formatted and do not need to be formatted out of the box. Memory cards are formatted with the following standards: SD/microSD 2GB or lower FAT16 SDHC/microSDHC 4GB to 32GB FAT32 SDXC/microSDXC 64GB or higher exFAT CompactFlash up to 128GB FAT32 CompactFlash 256GB exFAT Reformatting may clear file system corruption and quickly erase everything on the device. If re-formatting is needed, follow the steps below.

WARNING: Backup all your data before formatting. Formatting will erase all data on the memory device.

Formatting your memory device: 1. Double-click My Computer, or Computer (for Vista and Win7) 2. Right-click the drive letter associated with your memory device, then select Format (in the sample image below, we right-clicked on H:).

WARNING: Make sure you select the correct drive letter.

3. Select a File system type. - FAT - FAT32 - exFAT

4. Ensure "Quick Format" is checked

5. Click Start.

NOTE: exFAT is supported natively in WIN7 and WIN8. You will need to download a patch for Windows XP or VISTA to format a 64GB or larger device.

Reference: Operating Systems that Support the exFAT File System

If you have a problem formatting, you can try to Format using Disk Management.

NOTE: If the above steps do NOT resolve the problem or if the lock switch is missing or broken, please back up your data and request a replacement using our online web form.

Differences between FAT and NTFS Should I format my device in FAT or NTFS?

FAT is a primary computer file system for various operating systems, mostly DOS, including DR- DOS, OpenDOS, freeDOS, MS-DOS, Microsoft Windows (up to and including Windows Me). FAT is also used for removable flash drives and memory cards.

File system is a method for storing and organizing computer files and the data they contain to make it easy to find and access them. The chart below shows in what FAT system a flash drive or memory card should be formatted.

up to 4GB- 64GB and

2GB 32GB above Default format for memory FAT16 FAT32 exFAT cards and flash drives

NTFS NTFS is the standard file system of Windows NT, including its later versions Windows 2000, Windows XP, Windows Vista, Windows Server 2003, and Windows Server 2008, Windows 7 and Windows 8. NTFS is intended for use in Windows system drives (Hard Disk Drives and Solid State Drives).

NTFS has several improvements over FAT such as improved support for metadata and the use of advanced data structures for reliability, and disk space utilization, plus additional extensions such as security lists and file system journaling.

Notes for Flash Drives: - Formatting the flash drive as NTFS will make it unwriteable on a Mac computer. Most Mac computers can read NTFS, but not write. - NTFS is a journaled file system, this creates more read/write activities. Therefore, it MAY decrease life expectancy of your flash drive. - Once the device is formatted as NTFS, you MUST use "Safely Remove Hardware" to remove your device.