Macintosh Classic doesnt read disks

1. Is there a complete System 7.5 (including a PC Exchange control panel) on the internal hard disk?

2. You mentioned another floppy drive. Does this mean that you have an external floppy drive that is, or could be, connected to the DB-19 floppy drive port?

3. What kind of bootable floppy disk is available? 800K or 1.44 MB? System version? When this floppy is used as a boot disk in the internal floppy drive, does the Macintosh Classic start up properly (showing a floppy icon top right, and a hard disk icon below)?

4. Any screen photos?

5. Do you have access to another (pre-1998) Macintosh computer with a built-in floppy drive (if yes, model)? A Windows PC with a floppy drive?

Macintosh Classic: Technical Specifications

The Macintosh Classic is capable of reading/writing/formatting both 800K and 1.44 MB Mac-formatted floppy disks. In addition to this, with System 7.5 and an active PC Exchange control panel, 720K and 1.44 MB PC-formatted floppies can be handled.

Could you be a bit more specific about the disk types that you are referring to? Would it be correct to assume that the "system disk" is the internal hard disk drive, or is it possibly a floppy containing a valid system folder?

I used an external floppy drive because internal doesn't work

is this:

a) an Apple-brand external floppy on a cable with a DB-9 connector, -OR-

b) just any old USB drive? (these are ALL 1.44-only).

So your macintosh Classic boots from a 1.44MB floppy disk, but only when inserted in the External Apple floppy drive?

¿And the Internal floppy drive is not able to read or write anything reliably?

All I could suggest is trying to find a "cleaner" diskette.

You can use the DB-25 jack on the back to attach a modest-sized SCSI hard drive if you wish. These are no longer being produced. if you need one, I may be able to put one together for you.

To begin with, I guess that you have tried resetting the PRAM (press and hold down the four keys Command+Option+P+R at startup until the startup sound has been heard a second time) and rebuilding the Desktop (press and hold the two keys Command+Option at startup). Also, any change if you start up with Extensions off (the Shift key depressed at startup)?

A Macintosh Classic (but not the Classic II, nor any other "classic" Macintosh computer) has the ability to start up from ROM (by pressing and holding down the four keys Command+Option+X+O at startup). Just for troubleshooting, would booting from ROM (a special System 6) allow a Macintosh-formatted 1.44 MB diskette (without and with files) to be recognised?