I am having an issue getting an operating system to install on two old Macs, an LC 475 and a Performa 630. No matter what manner in which I try to install System 7.5.3, I get an error at some stage during the install. The exact same disks worked with my LC III, but not my LC 475 or Performa 630. I will be going about my business and swapping disks in and out and suddenly (and at different stages each time), I'll be asked to "Please insert the disk: Install Disk 1". If I do that, it closes out the install and it says the following: "An error occurred while trying to complete the installation. Installation was canceled, leaving your disk untouched." So, thinking it could possibly be my floppy disks (though unlikely, since the same ones worked on the LC III), I used another copy of the System 7.5.3 install disks and moved them over to my Floppy Emu. I have the exact same problem. And as I say, this happens with both my LC 475 and Performa 630. They have different hard drives installed and each of them had working OS's prior to my attempts to wipe the drives and put fresh installations of 7.5.3 on. It's worth noting that I have an original copy of System 7.6 that I must have gotten while my mom was still working in education; I've tried those disks and had the same result. I have initialised the drives, tried partitioning the drives, repairing the drives, etc. etc. It seems that no matter what I try to get an OS onto either of these machines, I hit this stumbling block. One more point to add: my LC III has a SCSI2SD adapter with SD card, whereas the 630 and LC 475 have standard SCSI hard drives. Does anyone have any ideas as to what might be causing this and what steps I might take to solve it? Thanks!