Is there an Intel processor generation requirement that should be listed in addition to the core minimum requirements? For instance, Haswell and newer?

Not that I'm aware of. The only requirement is virtualisation to be enabled in BIOS.

I think I found my issue. I have a Dell T5610 and a Dell T5600. The T5610 will install Harvester, but it doesn’t work right… very strange behavior that I think might have something to do with Dell’s firmware. The T5600 works fine… I think, still testing. I wondered if there was an issue with older processors, but that doesn’t seem to be the case; as both systems have the same Sandybridge Xeon with the only difference between the two being their mobo and firmware.

Latest BIOS?

Yeah, I updated it the other day. From what I can tell A19 is the last update available for it, and that’s what I’m running.