This is concering my G4 Desktop that was running OS X 10.4.11 (Tiger), as is my G4 Powerbook on which I'm typing this. What happened is my fault. I was getting rid of unneeded files, when by accident I deleted an entire Systems Library; even though it prompted for a system administrator password. As soon as I hit "Empty Trash" it was: "Uh-oh, bad move." Anyway, what's done is done, and I'm trying to get it up and running. Basically, pressing the Start button gets the Startup Chime followed by a gray screen with the Apple icon and the forever circling gear icon. I have spent the past couple of days browsing the MacRumors Forum, testing out all suggestions for similar issues - but nothing has worked. Below is a list of the unsuccessful strategies: 1. FIREWIRE: Connected with Firewire to my Powerbook G4 and held "T" - no luck. It does not mount on the Powerbook - the monitor is a Grey screen with Apple logo and circling gear icon. 2. STARTUP CD - They are lost. I can't contact Customer Support because even though I bought the extended AppleCare, the three year warranty period expired several months ago. 3. SAFE BOOT: Reboot holding down the <Shift> key. No luck at all - just the grey screen, apple icon, and circling gear icon. 4. SINGLE USER MODE: Reboot with Command and <S> key until a command line interface comes up. No luck - the command line interface never comes up (which I've read follows "###"). The cursor is frozen and does not respond to input from the keyboard. Below is some of the text that is frozen on the screen when I try to reboot in Single User Mode: Apple Extended USB Keyboard: family specific matching fails Apple Optical USB Mouse: family specific matching fails IOUSBInterface: family specific matching fails ApplePMU: : CLOCK RESET! PMU WAS PROBABLY RESET SOMEHOW!! Security auditing service present BSM auditing present disabled rooting via boot-uuid from /chosen: 80D36B51-E8AD-38AF-8CC8-4E9617097D00 WAITING ON <DICT id="0"><key>IOProviderClass</key><string ID="1">IOResources</string>key>IOResourcesMatch</key><string ID="2"> (here it cuts off) Got boot device = IOService:MacRISC2PE/pci@f4000000/AppleMasRiscPCA/ata-6@D/AppleKauaiATA/ATADeviceNub@0/IOATABLockStoragDrive (cuts off) bsdROOT: DISK0S9, MAJOR 14, MINOR 10 LOSAD OF /SBIN/LAUNCHD, ERRNO 2, TRYING /SBIN/MACH_INIT LOAD OF /SBIN/LAUNCH FAILED, ERRNO 2 If anyone could please suggest a do-it-myself solution, I would be deeply appreciative.