You can try and format 1.2 HD floppy as 360k if you want. At least you'll know if it's usable at all in a PC. In general HD floppy will behave as a very good quality DD disk. The other way around is not always so easy, some FDDs are hardwired for HD mode and will refuse working with DD/QD media, or (if the floppy sensor is also missing) might just try and error out. This is quite common for very late 3.5" models when manufacturers tried all kinds of cost cutting measures as the floppies were phased out of existence.

Thanks for your advice, but I'm afraid I don't have much interest in 360k disks. I suppose it would be nice to know if the drive works though, but I won't be selling anything anytime soon. Are these Staugart drives of any value?

Sorry about not replying for a while. I completely forgot about this. Feipoa, I don't think the Shugart drives are off too much value. At least when I bought mine on eBay, they were slightly cheaper than others selling theirs and at the time I had no idea it was a Shugart. I ended up getting a Cannon MD 5501 drive and I been happy with that.

Sorry to necro this post, but I was searching for a solution for this issue and I seem to have gotten my drive to work. Guess it's ok to bump threads to post solutions, right?

My drive is a TEAC FD-55GFR and I kept getting the 'general failure error' on my Laser Turbo XT3 (8086). I suspected I had to set the jumpers for this system, so I refered to this document. First off, make sure your Drive Select (DS) is set correctly. My FDD controller was able to figure out the right drive letter when I set this to DS1. Even paired with another drive (3.5) also set to DS1, it used the twist in the cable to figure out the right drive letters.

Then I turned to the RY and DC jumpers. DC is normally used for AT class systems (286, 386, 486), so I had to set mine to RY. This however still wasn't enough to get the drive to read disks.

Then the LG jumper: The document mentioned that for an AT class system, this jumper needs to be OFF. So, I figured it might be worth setting to ON for an XT-class system. Still comes up with 'general failures', however.

At this time I was getting desperate and dug into some of the more misc. settings such as jumpers I and IS. The document mentioned that jumper 'I' should be set ON and 'IS' set to OFF to enable the dual speed mode on this drive.

Oddly enough, that did the trick. I guess the disc was spinning too fast for the head to read the data and my controller wasn't able to figure that out by itself. Forcing the Dual mode to be ON, seemed to have fixed the issue. I've not gone back to see which of the other jumper settings affected the drive, so you might not need to set the others to fix your drive.