Trouble upgrading iMac (27", mid 2011) to High Sierra
I am trying to upgrade my iMac (27", mid 2011) currently running 10.11.6 (El Capitan) to High Sierra 10.13.6.
All information I can find tells me I can do this but when I go into my software updates it does not show it.
I have downloaded 10.13.6 but when I click it to install it tells me I need 10.13. Do I need to upgrade to Sierra before upgrading to High Sierra?
I can't find 10.13.
Earlier Mac models