Emacs sometimes can't open load file -

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• cannot open load dired-details 1 answer

i'm using emacs, , of packages install using elpa. works fine, , well. however, there 2 packages normal

(require 'package-name) (do-stuff-with package-variables) 

doesn't work. in particular, yaml mode , sr-speedbar.el give me error "cannot open load file, " on startup.

the odd thing if open .emacs , evaluate line hand, does work. file exists, readable, etc., emacs can't find during startup -- later. i've done googling, nobody seems have problem.

probable duplicate of cannot open load dired-details

add line

(package-initialize) 

to beginning of .emacs .

or see variable

package-enable-at-startup