My computer got the flu (probably a w0rm) that infected the c drive and left it unusable in about 1 day. I won't name it here, but it was discussed recently over on the GW Computer Help forum. DH is pretty smart with this stuff, but we had to get someone to fix it. Luckily, the photos on it were salvaged. I back up all my photos on CDs at the end of every month for DS, and also on an external hard drive for me, so would have only lost this month. These things can attach to anything saved on the computer, so could be spread with flash drives, etc. It's hard to tell where they come from, so there's not really any advice to avoid them. I had all the anti virus stuff and updates, but they didn't catch it. All I can say is BACK UP anything you don't want to lose. I'll be loading photos on a separate drive from now on. Linda