MacBook can't complete installation of El Capitan without battery?
I have a 15" MacBook Pro Core i7 A1286 (mid 2012)
I'm unable to complete the installation of El Capitan. I only have the HD & RAM memory installed (no battery).
Other Mac OS-X Versions are installing OK (even Windows). But, when I try to upgrade to El Capitan it never finishes the update. Also, it will not install via USB thumb drive.
I have tried everything!
I wonder is the problem I don't have the battery installed?