I [was] having the same problem as described in this old thread by MarkT [from 15 Sept 2011]. Why hasn't this problem been resolved in the IDE SD library?
For reference, all of the example sketches in the SD library run fine, so the SD Card is formatted ok, and has files on it to be read, my Arduinos work, the CS pins are set appropriately, D10 is set to OUTPUT, &etc, &etc, &etc.
Notes: - IDE v.1.0.5 - SanDisk Micro SD card, 4GB and 8GB - tried on 2 different UNO boards, one board with SD socket built-in, and also using Sparkfu SD shield
. I finally fixed the problem by tracking down the 3-YO thread, and following MarkT's comments, by adding the following commands at the end of the example sketch, eg CardInfo, [code] digitalWrite(8,HIGH); SPI.transfer(0xAA);[/code] Why hasn't this problem been resolved in the IDE SD library? Why isn't there a note on the Arduino SD pages telling how to fix it?