So I had same problem before, like 10 lectures ago, but after second or third attempt, I managed to import assets created in blender. This time third attempt failed to and I would rather solve my problem for good.
My problem goes like this - I drop unity package file into unity, I click import, and as soonest blender name pops up in whole process, my system goes down.
Then each time I reopen my project, same thing happens at the same stage of processing it’s files.
Oh right. I actually “solved” my problem, by having blender open, when reopening unity project.
Why that worked?