Dear List, I found the 31 errors and fixed them. Using Idefrag, it failed three times to fully defrag my hard drive. Each time, it told me which file was the problem. Deleting these files, and their "siblings" (just in case) allowed Techtool Deluxe to complete a surface scan without errors. Idefrag completed its work without errors also. Still have the "invisible folders" question so if someone has a hint..... Thanks. Lee 21 Dec 2006. Dear list, I have "won" the trifecta. In the last 2 weeks, my LCD display failed, so did my internal hard drive, and my logic board went while restarting with the failed hard drive (which was unknown to me.) Did have a major backup completed 24 hours before the drive failed... Now, have a new, bigger hard drive, and a "new-to-me" logic board. Display maybe a week+ away. So, after putting a basic system 10.4.8 on the internal hard drive, ran techtool pro and the surface scan test showed 31 errors. Erase and reformatted using Disk Utility and restored the drive. Still have the 31 errors. Any idea how I can get rid of these errors. I believe I want to map out the failed segments and I thought that disk utility did that, but not 100% sure. And, during restoration, three normally invisible alias folders are visible: etc, tmp, and var. Used Cocktail to make all invisible files and folders at the root level visible, and then invisible. They remained visble. So, any suggestions to make these invisible again? TIA Lee