Thanks for your suggestion! The problem lies in a variable I set which
points to the directory of my Dropbox folder, to ensure emacs portable on
different OS.

When I have the bibliography link in the org file, the
(org-ref-find-bibliography) will return the absolute path to the .bib file,
which in my case is
/home/kai/Dropbox/bibliography/references.bib
But if I do not have the link, it returns
~/Dropbox/bibliography/references.bib

It seems some modules are resolving the '~' while some others are not.

Cheers,
Kai


On Sun, Dec 13, 2015 at 2:15 AM, John Kitchin <jkitchin@andrew.cmu.edu>
wrote:

> That sounds odd.
>
> What is the output of this src block in your file?
>
> #+BEGIN_SRC emacs-lisp
> (org-ref-find-bibliography)
> #+END_SRC
>
>
>
> Kai Chen writes:
>
> > Dear list,
> >
> > I just got to know org-ref, and I followed the github help page to
> manually
> > install the package and set the default path similar to the configuration
> > provided in the follow link:
> > https://github.com/jkitchin/org-ref
> >
> > And I installed all the dependency packages like helm-bibtex, hydra etc.
> >
> > But when I am citing (using "C-c ]") an existing entry which is in the
> > default references.bib file, I can see the entry after I stroke the
> > command, but after I selected it and pressed enter, when the cursor is on
> > the link, the mini-buffer says:
> > !!! No entry found !!!
> > But previously the org-ref-helm-insert-cite-link properly showed that
> > entry. This can only work when I manually add a bibliography link at the
> > bottom of the file, which means org-ref is not using the default
> > bibliography file.
> >
> > So what should I check to fix this issue?
> >
> > Thanks for your help!
> >
> > The following is my configuration of org-ref:
> >
> > #+BEGIN_SRC emacs-lisp
> >   (setq org-ref-path (concat my-dropbox-path "software/org-ref/"))
> >
> >   (setq reftex-default-bibliography (concat my-dropbox-path
> > "bibliography/references.bib"))
> >
> >   ;; see org-ref for use of these variables
> >   (setq org-ref-bibliography-notes (concat my-dropbox-path "bibliography/
> > notes.org")
> >         org-ref-default-bibliography (concat my-dropbox-path
> > "bibliography/references.bib")
> >         org-ref-pdf-directory (concat my-dropbox-path
> > "bibliography/bibtex-pdfs/"))
> >
> >   ;; *** helm-bibtex
> >
> >   (setq helm-bibtex-bibliography (concat my-dropbox-path
> > "bibliography/references.bib"))
> >   (setq helm-bibtex-library-path (concat my-dropbox-path
> > "bibliography/bibtex-pdfs"))
> >
> >   ;; open pdf with system pdf viewer (works on mac)
> >   (when (eq system-type 'darwin)
> >     (setq helm-bibtex-pdf-open-function
> >       (lambda (fpath)
> >         (start-process "open" "*open*" "open" fpath))))
> >
> >   ;; alternative
> >   ;; (setq helm-bibtex-pdf-open-function 'org-open-file)
> >
> >   (setq helm-bibtex-notes-path (concat my-dropbox-path
> > "bibliography/helm-bibtex-notes"))
> >
> >   (global-set-key [f10] 'org-ref-open-bibtex-notes)
> >   (global-set-key [f11] 'org-ref-open-bibtex-pdf)
> >   (global-set-key [f12] 'org-ref-open-in-browser)
> >
> >   (add-to-list 'load-path org-ref-path)
> >
> >   ;; make sure you have dash, helm, helm-bibtex, ebib, s, f, hydra and
> > key-chord
> >   ;; in your load-path
> >   ;; auto-install dependencies
> >   (require 'org-ref)
> >
> >   ;; optional but very useful libraries in org-ref
> >   (require 'doi-utils)
> >   (require 'jmax-bibtex)
> >   (require 'pubmed)
> >   (require 'arxiv)
> >   (require 'sci-id)
> >
> > #+END_SRC
>
> --
> Professor John Kitchin
> Doherty Hall A207F
> Department of Chemical Engineering
> Carnegie Mellon University
> Pittsburgh, PA 15213
> 412-268-7803
> @johnkitchin
> http://kitchingroup.cheme.cmu.edu
>
>


-- 
Regards

Multi-Agent System Lab
University of Science and Technology of China

K.Chen