Hello, many thanks to Bernt Hansen for finding the root of my problem. Here is a recipe to unhappiness: Start with two files a.org and b.org which are part of some files you have created with Org-mode in mind for efficently producing high quality HTML content. Set up Org-mode to use ids for links; do an org-store-link somewhere in file a.org, then an insert-store-link somewhere in file b.org. Enjoy short-lived happiness that everything works after exporting to HTML. Then: delete ~/.emacs.d/.org-id-locations This is a good way to simulate this common scenario: transfer your org files to another system, by preference with a version control system so you can be sure the files are identical on both systems and then continue working on that computer; keep in mind: this is the default state of affairs when working in a team! Also note that .org-id-locations uses absolute path names, so syncing that file across different user work stations will seldom work. Now observe that after exporting to HTML *none* of your ID based links work that refer to locations outside the originating org file. Moreover, observe that Org-mode certainly must have noticed something did not work and failed to mention it. org-id-update-id-locations will not help you, unless (a) you remember to use it (preferably before you have already put HTML files with broken links online; this goes for your co-workers, too!), (b) files a.org and b.org happen to be agenda files or (c) happen to be mentioned in "org-id-locations" (this I learned from "describe function: org-id-update-id-locations"). None of the above is likely. Org-mode for HTML publishing is an excellent tool (for lots and lots of other things, too, of course) and I think using globally unique ids is, in general, a great idea. This is why I get a bit emotional about this id link business (sorry). Here are some suggestions: - expand the use of ids, so that, in analogy to other links, the inserted link can also contain a file name if it refers to another org fileD, maybe like this: file-id:some-file.org#8329AEF0-4885-486A-A1B6-BB82B3E92184 - if an id is unknown, search all files in the current publishing project, using the same selection of org-files that will also be used for project-based publishing - be verbose about links that could not be resolved, warn and potentially stop processing at that file (and while at it, also complain about unresolved macro definitions and finish with a summary line) - mention in the org-manual that using ids is not recommended for using links between different files because they break so easily (this is hardly an option, is it?) Let me emphasize that I am really generally a very happy org user and I am quite willing to contribute (as far as I can) to a solution to what I think is a problem with id-based links. Warm regards, Stefan On 18.08.2010, at 19:15, Bernt Hansen wrote: > Stefan Vollmar writes: > >> [...] >> >>> I think you need to look in the ~/.emacs.d/.org-id-locations file. This >>> maps link ids to files. >>> >>> -Bernt >> >> I think it is very likely that this is part of problem - I synchronize >> the directories containing my org-files and have, so far, done nothing >> about "~/.emacs.d/.org-id-locations". >> >> What is the best way to deal with this? >> - Synchronize? >> - Delete? >> - Force re-generation? > > I think you can just regenerate the file with a call to > > M-x org-id-update-id-locations > >> I have just taken a look at that file. It seems to map one id to one >> file. How does that help Org-mode if I rename an org-file that >> contains an id? > > This will probably make your ids and files out of sync so they don't > work for links in those files anymore. Regenerating the list for all of > the files you have with id links should fix the problem. > > I use the feature but don't rename my org files so I've never run into > this issue (if it is one). -- Dr. Stefan Vollmar, Dipl.-Phys. Head of IT group Max-Planck-Institut für neurologische Forschung Gleuelerstr. 50, 50931 Köln, Germany Tel.: +49-221-4726-213 FAX +49-221-4726-298 Tel.: +49-221-478-5713 Mobile: 0160-93874279 Email: vollmar@nf.mpg.de http://www.nf.mpg.de