Hey Wolf,
You say that after the format the drive is not seen by os3.1 right? So it did work before, and is yes what did you use IDEFIX or IDEFIX '97.
Some also prefer AmiCDFS from aminet (no costs) I hope you have acces to that source in some way.
Never forget that the cdrom could also be broken wich may cause in to not mounting the cd.
Greetings Henk
p.s. And welcome back
