[thijson]

Windows 3.11 was pretty unstable, because it wasn't using protected mode. I remember how unstable the Macs were back then too before the introduction of OSX.

Applications also had to voluntarily give up control of the CPU, cooperative multitasking. That's bad when an application crashes and takes down everything with it.

[p_l]

Windows 3.x could (and defaulted to where possible) to running in "386 enhanced" mode which actually used protected mode, IIRC.

The problem was that the Win16 part ran all in one address space, and the separation support was mainly used to handle DOS windows.