Tech Tool Pro.
There really is no need to defrag your drive when you are running in a UNIX environment. Under OS X, the disk is defraged when software updates are installed.
Also, under UNIX, there are certain files that need to be in a certain place. Defrag has a nasty habit of moving them to places unknown.
Step away from TTP.
Now that you have booted in to OS X from the internal, run Repair Disk Permissions and see if that makes any difference. Disk First Aid would be an idea too.
I am not to keen on the idea that after you Jiggled and tapped the drive, it worked. That does not sound good at all.
Try the permissions thing first and get back with us
Good Luck
P
I have a G4 running 10.4.11. I was defragmenting my computer using TechTools Pro when after about 15hrs it froze. I was working from a partition created on an external drive and when I restarted it only saw the external drive. I tried restarting several times and still no internal drive. I opened my computer, giggled the connectors and tapped the drive a couple times. I restarted and there it was. Unfortunately pretty much nothing is working. Most of the files and or programs wont open. I click to open and nothing happens or with some applications I get a message certain files are missing. The other unfortunate problem is that I don't have my original Tiger DVD. (Believe it or not, it was stolen when my car was broken into a year or so ago.) I was thinking I should go out and buy Leopard but wanted to get a few opinions first as to what the problem actually is. I'm concerned that the problem is that the drive itself has been damaged and that new software alone isn't going to fix it.

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