I've never had problems before with an update, but this time things have gone very wrong. When I reboot, I get the warning shown in the attachment. Also, I can't open Photoshop, as I get a similar warning shown in the other attachment. Then in Safari, the 'previous' and 'next' buttons aren't working. These probs are driving me mad, especially as I'm not very tech savvy. Any help would be greatly appreciated. Oh, and I'm using an iMac G4. Thanks!