Your xD-Picture Card is been disappeared and no longer been detected or wants to be formatted suddenly, even though seconds ago the card is still working properly?
Be sure the system tables of your card are damaged and no software can help. The only way to get the data/photos back, unsolder the memory chip, directly dump their raw data with a programmable chip reader and convert it to readable data. Their are only some specialists on earth, they are able to do this complicated procedure.
See also: data rescue software - data rescue problems

Formatting is required? The controller of the memory card is not in the position to inform the PC operating system about the characteristics of the memory card. Therefor the PC assumes, the memory card is not formatted and requests formatting. One could now think, the memory card problems are solved by formatting, unfortunately that does not work due to the damaged controller. Try it out, the PC will communicate, that a formatting is not possible. Finally this is then also a clear proof that any kind of software, also special formatting or rescue software!!, no more can access to the memory card.

This article is licensed under the gnu free documentation license. It uses material from the wikipedia article xD-Picture Card The authors of that article are listet here.

xD-Picture Card is a type of flash memory card, used mainly in digital cameras. xD originally stood for extreme Digital. The cards were developed by Olympus and Fujifilm, and introduced into the market in July 2002. Toshiba Corporation and Samsung Electronics manufacture the cards for Olympus and Fujifilm. xD cards are now sold under other brands, including Kodak, SanDisk, PNY, and Lexar, but are not branded with the respective companies' logos, except for Kodak. xD cards are used in Olympus and Fujifilm digital cameras and Olympus digital voice recorders; Fujifilm also made an MP3 player (xD-MP3) that used the cards. As of 2008, xD cards are available in capacities of 16 MiB up to 2 GiB.
Type M/M+ and Type H cards: The original xD cards were available in 16 MiB to 512 MiB capacities. The Type M card, released in February 2005, uses Multi Level Cell (MLC) architecture to achieve a theoretical storage capacity of up to 8 GiB. As of August 2006, Type M cards are available in sizes from 256 MiB to 2 GiB. However, the Type M suffers slower read-write speeds than the original cards. xD-Picture Card, 512 MiB, type HThe Type H card, first released in November 2005, offers higher data rates than Type M cards (theoretically as much as 3 times faster). As of 2008, Type H cards were only available in 256 MiB, 512 MiB, 1 GiB, and 2 GiB capacities. Both Fuji and Olympus discontinued the production of Type H cards in 2008, citing high production costs. The Type M+ card, first released in April 2008, offers data rates 1.5 times that of Type M cards. As of 2008, cards are available only in 1 and 2 GiB capacities. Olympus says that its xD cards support special "picture effects" when used in some Olympus cameras, though these software features are not intrinsically hardware-dependent. Type H and M+ cards however, are required in newer models to capture video at high rate (640×480×30). Due to changes in the cards' storage architecture, newer Type M and H cards may suffer compatibility issues with some older cameras (especially video recording). Compatibility lists are available for Olympus: Olympus America’s and Fujifilm’s. The newer cards are also incompatible with some card readers.
Detailed specifications: The detailed specification for xD cards is tightly controlled by Olympus and Fujifilm, which charge licensing fees and royalties and require non-disclosure agreements in exchange for the technical information required to produce xD-compatible devices. The memory format used by xD cards is not well-documented. It is difficult to study it directly, since most camera devices and most USB card readers do not provide direct access to the flash memory. Since the cards are controller-less, cameras and card readers must perform wear leveling and error detection themselves, and they normally hide the portion of the memory which stores this information (among other things) from higher-level access. However, a few models of xD card readers based on the Alauda chip do allow direct access (bypassing the above mechanisms) to an xD card's flash memory; these readers have been reverse-engineered and Linux drivers have been produced by the Alauda Project, which has also documented the on-chip data structures of the xD card. According to this information, the xD card headers are similar to those used by SmartMedia, and include information on the manufacturer of the chip.
Raw hardware: At the raw hardware level, an xD card is simply an ordinary NAND flash integrated circuit in an unusual package. Comparing the pinout of an xD card to the pinout of a NAND flash chip in a standard TSOP package, one finds a nearly one-to-one correspondence between the active pins of the two devices. xD cards share this characteristic with the older SmartMedia cards, which are also basically raw NAND flash chips, albeit in a larger package. xD cards and SmartMedia cards can be used by hobbyists as a convenient source of NAND flash memory chips for custom projects. For example, the Mattel Juice Box PMP can be booted into Linux using a modified cartridge containing an xD card with the boot image written to it. Additionally, SmartMedia and xD card readers can be used to read the data off of NAND flash chips in electronic devices, by soldering leads between the chip and the card reader.
Panoramic mode: Olympus-branded xD cards are the only ones that support Olympus cameras' panoramic function. Although they store data identically to other manufacturers' cards, Olympus intentionally disables this feature in the hopes that buyers will purchase their cards (a form of vendor lock-in). However, it appears that the card manufacturer information is simply stored in the flash memory, in the Card Information Structure (described in the Alauda Project's documentation, see above). Thus, it is possible to alter another brand of xD card to present itself as Olympus xD card by accessing the raw flash memory.