Bought a lot that included hundreds of old floppies but when I started to test them with the 500 that was in the lot, it started out fine but after a while the drive refused to read the floppies, even 100% good floppies that works in another drive I had.
I switched to that drive and same thing happened; it worked for a while then the disks started to get read & write errors and later the drive died completely. This was repeated a third time with another drive that was in the lot.
I now have three drives that seemingly are broken; two that refuses to boot, just three chugs and then nothing and one that boots but get validation error and then read & write error and while the two drives that were in the lot were somewhat untested and could have been on life support, the drive I had, albeit a modified PC-drive, worked flawlessly up until then.
I need to rectify this so it's a bit urgent; have these old floppies ruined the drives?
Dare I test them in yet another drive? Is it possible to ruin drives at all with old floppies, the surface looks okay and I tried to clean the heads on one of them with IPA without result.
Could it be a coincidence, that all three drives died at the same time due to something else?! I don't know