Chosen Solution
I have been trying to sign in on my old Macintosh 1400cs/166 however I have forgotten my password and I have tried holding down different keys etc. But it has not worked if anyone knows a way to bypass this or if anyone knows how to factory reset my mac I am open to that as well. Thanks. James
Here is a link I found giving some instructions for bypassing the password in Mac OS 9 (I think the Powerbook you have supports OS 7.5 to OS 9.1). I don’t have much experience with this older OS, let me know if this helps!
Unfortunately I do not have the os disc so I will not be able to do this thanks for the suggestion