Weird! I got my friends computer to dual boot, but what a rigmarole.
Firstly FIXBOOT doesn't create BOOTSECT.DOS. Ah ha, though: I'd played safe and used a thing mentioned before to save the W98 boot sector... bugger, I'd used it wrongly (not sure how), and my BOOTSECT.DOS was 512 bytes of zeros. So now I have a damaged W98 intallation. My boot menu came up, and I could boot XP, but I couldn't boot W98 without a valid BOOTSECT.DOS
Never mind, I'll use FDISK /MBR to put it right. But that didn't work, and - well - you wouldn't expect it to really because I'd overwritten the boot sector on C not the mbr. Strange thing though, after FDISK /MBR I lost my boot menu, and it booted straight to XP which was on the slave... wwhhatt!
Ah, well, I'll reinstall W98, so that I can have a second go at grabbing the boot sector. But, W98 was too clever. It noticed signs of XP, and set up a dual boot just like XP would, creating a BOOTSECT.DOS and adding a line to boot.ini to do it, except it did this on the slave.
Then for a while I thought I had it working. I rebooted, accidently let the W98 installation CD boot, but when it said HDD or CD I selected HDD. This gave me a boot menu, with XP and W98 on, and both worked. I could tell from the contents this was the boot.ini that lived on the slave.
But then I took the CD out, and this gave me the boot menu from the master, and I was back to XP working and W98 not. I triec copying the known good BOOTSECT.DOS from slave to master, but that didn't help. Going back to using the W98 installation CD and then selecting HDD still worked, but a direct boot didn't.
Just as a wild guess I changed the BIOS to boot from HD2 rather than HD1, and bing! it works. I haven't slightest idea how it is working one way and not the other, but I think I'm going to give up trying to understand it.
One more strange thing. Now I have XP running with the master/slave swapped in comparisen with how they were when XP was installed, so I should need to rename the discs. But no, XP sussed it for itself, somehow.
I must admit, if I was reading this, I wouldn't believe it. I'd think "no, he must have swapped the master/slave back again or something half way through". Yeh, yeh. Actually, anybody reading this, for the sake of your sanity, I strongly suggest, don't believe any of this. 😁