Upload never finishes but can be cancelled - stops at 75%

Continuing the discussion from PreForm hangs on "getting secure upload URL":

Me too, although it tends to be about 75% where it just stops. I can press the back button and cancel it, it just never finisheds. It seems to do it on our internal network and when we’re at home. Last time switching the printer off and disconnecting it worked but who knows if this is just chance. I wonder if there is some sort of memory bug.

I’ve noticed the printer goes “offline” quite a bit. Usually when this happens, if you go to the printer’s wifi settings you’ll see it’s dropped its network connection. Cycling the printer’s wifi connection off/on usually corrects this.