Silly me, I decided that I had to upgrade an old, original blue iMac because I wanted to try for video conferencing. It had (yes had!) 8.5.1 onboard and I wanted to put 9.2.1 on. I saw a thread that some people had put OSX on without upgrading, but I thought 'one step at a time".

To cut a long story short, no matter what I did, it would not let me install System 9, but something had also happened and the mouse was no longer activating any icons other than in the top strip. So, I thought, re-install System 8.5. Nothing on the computer of great importance, so a complete erasure of the hard disk and the luxury of willingly and happily starting from scratch. Unfortunately, when I start up from the System 8.5 disk and try to install, it only lets me choose the country and then goes into an error message "System error -36 occurred".

Can some kind person please give me a clue as to what I can do to get it going again?

Thanks so much