Having problems with your SD card reader with Vista? You might want to check out KB
936825.
When you insert an SD card into a card reader on a Windows Vista-based computer, Windows Vista does not detect the SD card.
This issue occurs if the following conditions are true:
The SD card does not support 1.8 volts and the SD host controller uses 1.8 volts. Typically, most SD cards use 3.3 volts.
When you insert an SD card or an SDIO card into the card reader on a Windows Vista-based computer, Windows Vista may not detect the SD card or the SDIO card. This issue occurs because of a timing issue with the SD host controller.
When you copy more than 4 gigabytes (GB) of files to a Secure Digital High Capacity (SDHC) card, some files may be corrupted. You do not experience this issue if you copy less than 4 GB of files to the SDHC card. This issue may occur because the Windows Vista SD driver does not correctly process more than 4 GB of addressing.
An SD card may occasionally stop responding after a Windows Vista-based computer resumes from sleep (S3) or from hibernation (S4) two times.
For example, you experience this issue after you follow these steps:
1. You put the computer to sleep or into hibernation.
2. You start the computer from sleep or from hibernation.
3. You copy files to the SD card or from the SD card.
4. You put the computer to sleep or into hibernation.
5. You start the computer from sleep or from hibernation.