Floppy disk recovery.
Yes, even those old ones.

You cleaned out a closet, a desk, an attic, or a deceased relative's house and now you have a stack of 3.5-inch disks labelled things like "Family Photos 2001" and "Tax Docs."

The good news: floppy disks are surprisingly durable in storage. They degrade, but slowly. A disk that sat in a desk drawer for twenty years has better odds than you would expect, because it was kept at a stable temperature away from magnets and moisture. Attic and garage storage is harder on them — heat and humidity accelerate oxide degradation — but even those are frequently readable.

I image every disk at the flux level, which means I am capturing the raw magnetic signal rather than just asking the drive to read it the way a computer would. Weak signals that a USB floppy drive gives up on are often recoverable from a flux image.

You bought a USB floppy drive, inserted the disk, and got nothing — an error, a request to format, or the drive just spinning endlessly.

That does not necessarily mean the disk is dead. Consumer USB floppy drives have very little tolerance for weak signals. They either get a clean read or they fail, with nothing in between. The drive is designed to read fresh, healthy media, not twenty-year-old disks with degraded magnetic coating.

Flux-level imaging with a Greaseweazle works differently. Instead of asking the drive controller to interpret the data, it captures the raw magnetic transitions directly from the disk surface. Weak spots, timing drift, and partial signal loss that make a USB drive give up are often recoverable from the raw flux data, because the signal is degraded but not gone.

The metal shutter is bent, the disk smells musty, there is visible mold on the cookie (the magnetic disk inside the shell), or the shell is cracked.

Mold is the most common physical problem on old floppies, especially ones stored in basements or garages. The mold itself usually does not destroy the magnetic signal — it sits on the surface. But inserting a moldy disk into a drive drags the mold across the read head and the disk surface, potentially scratching both. The disk needs to be cleaned before any read attempt.

A bent shutter is usually cosmetic and can be straightened or removed — the shutter is just a dust cover. A cracked shell is more serious because the magnetic disk inside may have shifted or been exposed to contamination.

The disk spins, something reads, but the files are gibberish, the names are wrong, or the computer says the disk is blank when the label says otherwise.

Floppy disks were used by every operating system from the mid-1980s through the early 2000s, and they did not all agree on how to lay out data. A disk formatted on a Mac running System 7 looks blank to Windows. An Amiga disk looks corrupt to both. A CP/M disk from a word processor is invisible to everything modern.

This is not damage — it is a format the operating system does not recognise. Flux imaging captures the raw data regardless of format, and the right tools can parse Mac HFS, Amiga OFS/FFS, Atari ST, and most other period formats.