melpa won't load on emacs windows

Question

I am using emacs on windows 7. Emacs is located on a usb on a university computer with no admin access but correctly loads the .emacs file. In my .emacs file I have

(custom-set-variables
 '(package-archives
   (quote
    (("gnu" . "http://elpa.gnu.org/packages/")
     ("melpa" . "https://melpa.org/packages/")))))
(custom-set-faces)

When I try load package-list I get Failed to download ‘melpa-stable’ archive.

Any ideas? Thanks in advance!