Hi, I'm feeling very dumb right now. I've got a PC/XT with its original MFM hard drive, and I bought one of those USB ISA cards that allows you to use flash disks on pre-USB capable systems.

I installed the card and copied over the driver from a floppy disk, and then I hastily added the relevant line into config.sys to enable the card, assuming it would just work (and I used the correct 4.2KB driver, not the other two) and unfortunately now the machine just hangs at boot, with or without the card installed. It says "Starting MS-DOS" and then nothing happens, presumably because something is wrong with the driver.

Stupidly, I didn't think to add a menu to config.sys to allow me to skip the driver, and even more stupidly, the existing config.sys contained the line "SWITCHES=/N" - which prevents you from pressing any of the keys that let you skip config.sys - and I didn't remove it.

I should be able to fix this by booting from a floppy disk and just modifying the file, but for some unknown reason, the only version of DOS that I can get it to boot from a floppy disk is PC-DOS 1.1, which doesn't let me access the hard drive because it's too big.

It doesn't help that I don't really have any known good 5.25" disks or drives, so I can't eliminate the possibility of it just being bad. I do have another 5.25" drive in another machine that I have tested to be capable of booting other versions of DOS, but bizarrely, it won't boot the PC-DOS 1.1 disk that works in the 5160???

So I'm stuck between possibilities. I could swap the 5.25" drive from the other machine into the PC/XT and see if it boots a newer version of DOS that can access the drive, although that would be very inconvenient for troubleshooting because I might have to keep swapping the drive back and forth between the two systems. I could (or perhaps should) buy a gotek and do the same thing with that, although I don't really feel like spending even more money right now, especially because I'd also need an adaptor to go from 34-pin to card-edge. I could put the MFM drive and controller in a newer system, but I don't even know if that'll work, or if it'll be possible to use the MFM drive alongside an IDE drive, and again, that could be a pain for troubleshooting.

I'm really not sure what to do here. I know in reality I should just get a gotek, but if there happens to be a way to fix the issue using the tools I already have at hand, then I would be very grateful to know.