I've had some disk errors (Missing thread record) on the 2GB drive in my Imac i7. After repairing with Diskwarrior the problem reoccurred after a few days. I did bad block test and everything was OK, so I was thinking it maybe was the OS (10.6.2) causing the error. I DL the 10.6.2 combo update,to do a reinstall but the installer won't let me install "Mac OS X Update Combined can't be installed on this disk. This volume does not meet the requirements for this update" -any suggestions?