You're welcome. Because SDXC cards are considerably more expensive than other versions of SD cards, this issue comes up much more frequently with SDHC cards. The original SD cards had a capacity of 1 GB or less.
The newly released Card Reader drivers are a high priority update recommended for all SanDisk. Windows® 8, Windows® 7, Vista, XP Pro, XP Home, 2008 and 2008 R2.
SDHC cards have a capacity of 4 to 32 GB. The most common problem with respect to SD cards I've seen in the forums in the past couple of years is an inability to read an SDHC card (4 to 32 GB) in an older card reader. The first card reader controllers capable of reading SDHC (4 GB or more) were built in January 2006 and the first cards hit the market in August 2006. A card reader made before January 2006 won't be able to read 4 GB (and larger) SDHC cards; it will be able to read SD cards that are 1 GB or less; and probably but not certainly will be able to read 2 GB SD cards (there were also some 4 GB SD cards, but you're not likely to find any of these today). More than you wanted to know:.
Windows Driver For Sdhc Card
Bottom line: if your XP computer was manufactured before 2006, you'll need to buy a new card reader to read pretty much any high capacity card you're likely to buy today. The good news: they're not very expensive - Do read the specs and at least some of the reviews before purchasing. In addition to capacity, you also have to be aware of the card's physical size.
Most but not all 'micro' cards will be sold together with an adapter that lets you insert it into a reader slot for full-size SD cards. If you don't have an adapter, be sure that your card reader says that it can be used with 'micro' cards. The same is true of 'mini' sized cards, although SDXC doesn't come in 'mini.' - LemP Community Moderator MS MVP (Windows Desktop Experience) 2006-2009 Microsoft Community Contributor (MCC) 2011-2012.