Insert your OS X installation disk or your Restore Disks, (Came with the computer) whichever has the latest OS on it.
Restart the computer, holding down the "C" key. the computer will start form the CD/DVD.
Start the installation process but when you receive the warning that you cannot install unless you change your options, choose to change the options.
Choose, Archive and Install from the list. DO NOT CHOOSE FORMAT AND INSTALL.
Proceed with the install.
On completion of the installation, you will have a new system folder, the old folder will still be there but will have been renamed.
All your data will be intact and all your settings will be as you left them.
Your OS will be out of date and will need to be updated immediately.
Other than that, there is nothing to do
P
I have an iMac G4 running Tiger! I accidently deleted my HD Library Folder. Some programs are not working right. There is nothing in the Receipts Folder. Someone said I have to do an Archrive & install, is this correct and how do I do this?
Thanks Eleanor

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