I've been having a horribly annoying problem when I "lock" my computer manually, or have it set to go automatically when the monitor goes off. It doesn't happen consistently, I have to leave the computer locked for a while to trigger it. Symptoms include all the icons disappearing from the start menu, and the inability to open anything. Since I can't open windows explorer, or anything else, I can't take screenshots of anything. Doubleclicking an icon on the desktop results in nothing happening, hitting windows key + e returns a dialog box with "The parameter is incorrect." Ctrl+alt+delete + log off, then logging back on fixes the problem. Sorry it's so vague, but it's difficult to troubleshoot the problem when I'm unable to do open any files. If anyone needs me to try stuff, I'll lock my rig overnight, and try stuff in the morning. Any ideas?