start it again and don't insert a floppy. Wait a bit and see if the flashing floppy icon with a question mark appears.

if it does then it is confirming that your hard drive is starting to go bad.

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if you are not familiar with opening and working on these macs then you will have to do some research.

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hard drives go bad for many reasons, but seems yours was working recently it could be many things. Rubber seals melting with age inside the hard drive cover, rubber stop for swing arm melting, bad connections etc etc

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I have got many drives working again but you have to do your homework first.

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you can do more damage if you don't know what you are doing

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