I updated my gear from the other device (notebook) via the same LAN. And it doesn't work on desktopPC that time.
I see, recomendations from support are not resolve problem. I see it now, I saw it two years ago. There's an unknown little thing which can do problem with update. It can be in registry, in a windows library, in a windows service (one of them is off), in a third party soft... I don't know. But will it work or not - nobody can predict.
My advice - just try another computer
(Sorry for bad English)
P.S.: Line6, thanks for helping, anyway your products is great)