I had the same problem with my w880i yesterday and - unfortunately - found no solution. I tried the memory stick in my k800i, too, and there it worked with absolutely no problem. And my PC is able too read the files on it. I formatted the stick, but the w880i still crashed, tried to reboot and still stalled while reading the SIM card (!). It told me "Insert SIM card (..)", which drove me mad first... So I fear, that this is a severe hardware failure. Any suggestions to solve this?