I am trying to install org-ref package but getting error
package-compute-transaction: Package 'emacs-25.1' is unavailable.
I searched Stack overflow, Stack Exchange Emacs, and github. I've found many solutions like this but isn't working for me.
I am using Emacs 25.1 in Ubuntu 16.4.
Edit: I am using Emacs 24.5.1 version.
I was able to install org-ref earlier but need to reinstall as it got corrupted.