How to reinstall OS 7.5 PM7200/120

Oh fun. You are missing one critical component. What about the original G5 installer discs? Are they there?

The PowerMac 7200/120 can install either the system specific System 7.5.2 it shipped with or newer retail discs up to Mac OS 9.1. For free, Apple makes available System 7.5.3 on floppy downloads from:

http://ftp.iinet.net.au/pub/apple/US/Macintosh/System/Older_System/System_7.5_Ve rsion_7.5.3/

Then that can be updated to 7.5.5 with these disks:

http://ftp.iinet.net.au/pub/apple/US/Macintosh/System/Mac_OS_7.5.5_Update/

You will need a copy of Disk Copy from your PowerMac G4's system and attach the USB Floppy drive to it to make the floppies from the .smi file, and a copy of Stuffit Expander for Mac OS 9 or earlier.

Mind you, you will also need enough 1.4 MB floppies to take care of it.

If you can find the retail Mac OS 9.1 installer CD or earlier retail installer CD you could install those on the 7200.

Note 7.5 was not terribly stable in terms of the internet because Open Transport didn't get the bugs worked out of it until System 7.6. Unfortunately Apple has not made those floppies or the CD freely available or later.

Mac OS 9 retail CD said in black print 9.0, 9.0.2, 9.0.4, or 9.1 on it, and looked like:

9.2, 9.2.1, and 9.2.2 do not work on the Powermac 7200/120.

Mac OS 8.5 looked like: http://thumbs2.ebaystatic.com/d/l225/m/mqYv_QwjITbw_uw9c5uyfZA.jpg

Mac OS 8.0 looked like: http://www.mac-s.co.jp/images/useditem/513/0308111-6.jpg

Mac OS 7.6 looked like: http://www.mac-s.co.jp/images/useditem/513/0308111-4.jpg

No version that is retail said Update, Dropin, or OEM on it, or the name of a Mac model on it.

The complete System 7.5.3 can actually be downloaded directly from Apple via the Older Software Downloads page: http://www.info.apple.com/support/oldersoftwarelist.html .

Click on the System Software Downloads link. Locate the files

System_7.5_Version_7.5.3/System_7.5.3_01of19.smi.bin

System_7.5_Version_7.5.3/System_7.5.3_02of19.part.bin

System_7.5_Version_7.5.3/System_7.5.3_03of19.part.bin

etc to

System_7.5_Version_7.5.3/System_7.5.3_19of19.part.bin

Please note that Disk Copy is not used in this case. Each download is floppy-sized, but this is only to make it possible to copy the files onto 1.44 MB diskettes for transfers. Alternatively, if the existing system folder has the necessary CD-ROM helper files, it is possible to burn a CD-R (at a low speed) with all nineteen files on a modern computer (Mac or PC) in an ISO format. That CD should then appear on the Desktop on the Power Macintosh 7200/120. Keep the MacBinary (.bin) encoding until on the receiving Mac.

The idea is to bring all files over to the hard disk of the Power Macintosh 7200/120. Once there, use an appropriate version of StuffIt Expander to decode the MacBinary (.bin). Place the nineteen decoded files (one .smi and eighteen .part) in a common folder. Double-clicking on the first file (the .smi) will mount the entire disk image. The installer can be found inside the mounted image.

If you do not have an early version of StuffIt Expander for Macintosh: With access to a Windows PC (capable of running a DOS program) with a floppy drive, you may want to try the following. Prepare an empty PC-formatted 1.44 MB diskette via FORMAT A: in DOS or the "full" formatting option under Windows. Download the MACDISK.EXE file from http://rrzs42.uni-regensburg.de/Macintosh/files/macftp.html . Run the MACDISK.EXE (DOS) program on the Windows PC. Follow the instructions on screen. The result will be a Mac-formatted (sic!) floppy that can be used on the Mac. This floppy contains a StuffIt Expander installer. Once installed, drag downloaded .bin files onto the StuffIt Expander program icon to decode them.

Also, if you need a bootable floppy (good idea), a Disk Tools PPC disk image file can be downloaded from Apple: http://download.info.apple.com/Apple_Support_Area/Apple_Software_Updates/English -North_American/Macintosh/System/Mac_OS_8.1_Update/Disk_Tools_PPC.img.bin .

In this case, Disk Copy 6.3.3 (the Make a Floppy command under the Utilities menu) is used to create a properly sector-copied floppy: http://download.info.apple.com/Apple_Support_Area/Apple_Software_Updates/English -North_American/Macintosh/Utilities/Disk_Copy/Disk_Copy_6.3.3.smi.bin .

Jan

Addendum

For clarity, neither a floppy nor a CD-R with System 7.5.3 files will be bootable. The Power Macintosh 7200/120 needs a working system to begin with (as it apparently already has). Once on the hard disk, the nineteen decoded files together constitute one large disk image.

It is also possible to use the bootable Disk Tools PPC floppy to erase the hard disk. However, one would then have to install a temporary system onto the hard disk (this could be a drag-copied System Folder from the Disk Tools PPC floppy). Before you decide to erase the hard disk, it may not be a bad idea to make backup copies of the existing CD-ROM extension and all its helper files onto a Mac-formatted 1.44 MB floppy disk. At the same time, it could be wise to make a backup copy of the existing PC Exchange control panel.

In order to start from a (bootable) system CD, try this: Insert the CD while the computer is running. Choose Restart from the Special menu. Press and hold the C key during startup. If there is a problem starting with the C key depressed, try the four keys Command(Apple) + Option(Alt) + Shift + Delete(Backspace). The boot disc should appear top right on the Desktop.

When the hard disk is not the boot disk any more (not top right on the Desktop), it can be erased (via a utility on a CD or on a Disk Tools floppy).

A retail System 7.6 CD contains a Drive Setup disk utility (in one of the folders) that can be used to erase the hard disk. You will also find a folder with disk copies on this CD. There are two Utilities disk images. One of them should be OK for your computer. In order to make a real floppy from a disk image, use the contained Disk Copy application (the Make A Copy button).

Jan

Addendum

>retail System 7.6 CD

This system is called Mac OS 7.6.

>two Utilities disk images

They may be called Utilities or Disk Tools. A tools floppy made from one of the images would be bootable.

If the computer has started from the CD, and the hard disk has been erased, it should be easy to directly launch the installer and install a fresh system onto the empty disk.

I was referring to an original Apple retail system CD, which is bootable.

>A retail System 7.6 CD contains a Drive Setup disk utility (in one of the folders) that can be used to erase the hard disk.

For computers with a SCSI hard drive, one would normally use an HD SC Setup disk utility. However, according to a text file on the CD, the included Drive Setup version is supposed to be used for all models with a PowerPC processor.

Well, you could get a legal system through the System 7.5.3 download from Apple (see above) without too much difficulty. The difference between 7.6 and 7.5.3 is not huge. The transfer of the nineteen System 7.5.3 files can be carried out on one CD-R (ISO 9660).