All began with switching out some bad looking electrolytic capacitors. Yes, the machine was running before and I'm pretty sure I didn't damage anything afterwards.

Now I have a "1780 Disk 0 Failure "error at boot. I don't know what went wrong, but I have the new caps in mind. I backed up everything from the disk and then I wiped it on my Windows 10 PC and tried to install the Diagnostic Partition and Setup on the Deskpro, but it still gives me that same error. At boot it takes some time to get from the Compaq splash screen to the 1780 error. When I boot from the Diagnostics Diskette, it now takes much longer, than I was used to, to show the first window from the Utility.

I can't seem to create new Partitions under DOS. It always gets stuck when I hit Enter after selecting option 1 (Create Primary DOS Partition). It definitely sees the disk and I analyzed the disk for defects with the Hitachi Feature Tool and SeaTools, but they reported no errors. I should also mention, that I use a down-sized SATA drive with an IDE adapter, but it doesn't have a jumper option for cable select, only master and slave. I read, that Compaq computers prefer cable select, but the strange thing is, that when I first set up the Deskpro I ALWAYS used master and it worked before. I reflashed the BIOS aswell with the SP8434, like I did the first time, when the Deskpro was still working. I also cleared the CMOS and checked the coin battery, if it was depleted, but no.

Please help. I was programming some software on that Deskpro.