Is there any way to install El Capitan on Y580 after mac os Sierra release? Upgrading in iStore to El Capitan is no longer available (unless you want to upgrade from snow leopard, if anyone uses it now) and downloading El Capitan upgrade app from sources other than iStore ends up with Invalid installation app error. Only machine I can use to make an USB is running Yosemite now, and I can't really get another one.
Sorry, if I'm writing in wrong thread, if so, please tell me and I'll write somewhere else, I just need to install OS X on my Y580 as quickly as possible, and lack of information about making USB boot drives puts me in a bit of impasse. Also if somebody answered this question so far, please point me just where to look for.