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Originally Posted by bigw00dy
I am getting this window when I try to open up a disk that contains images. The disk is from 2004 or so if that matters.
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First, write protect the diskette. Until you have eliminated other reasons for the problem, don't let anything write to this diskette.
Second, blowing air on the disk or inside the drive is useless. One problem that does occur is a magnetic deposit on disk heads. This can be cleaned with 90% alcohol and a Q-tip. But that means opening the drive. Instead move on to other options.
Third, diskette could have been written by a drive that was out of alignment. Therefore only that unique disk drive would be necessary to read diskette. Or diskette could be failing. Magnetic material does degrade with time - faster on some inferior diskettes. Repeated reads until the sector is read could be attempted using many different drives until one finally reads a signal strong enough to decode data. A disk that is properly aligned could be just off enough to read badly misaligned diskette data or, well try reading using different drives until one diskette / floppy drive combination finally works.
Fourth, of course currently used drive could be out of alignment, or has a weak data reading head. Again, try other drives.
Fifth, what the problem is. Formatting is a process where each data sector is magnetically defined. Each sector has a header that is written once by formatting, and then remains read only in normal use. Floppy drive reads this header, then either reads or writes data after this header. The header is how drive synchronizes to each sector's data AND confirms it is reading correct data. If that header cannot be read by floppy disk controller, then controller complains about address mark; does not know if data is good or junk. No address mark is a communication problem between what should be read only information on diskette and the floppy disk controller. Computer is simply reporting what it was reported by floppy disk controller.
Sixth, any attempt to rewrite that address mark will (obviously) destroy data which is also why that diskette must be write protected.
Seventh, it is possible to read all other data. But that requires special programs that ignore the bad address mark in that header. For example, that one sector could simply leave one and only one file defective.
Of course you know what computer wrote this diskette. This is not a file incompatibility problem. This is a problem unique between that diskette and that controller inside the floppy disk controller. Operating systems and file formats would be irrelevant to the problem. But some OSes have better tools to partially recover data. No reason to continue since information from above tests is enough for a first experiment.