Update: 2021-05-27

This is still getting traffic for unknown reasons. Today, in 2021, the problem is long solved. DEVONthink 3 syncs perfectly with itself and with DEVONthink To Go. Again, this is purely historical and not a reflection of the state of things today.

Also, I have no idea why this post is suddenly so popular again. Help me out and let me know how you found this page? I’d sure appreciate it!

Update: 2016-09-17

In July 2016, DEVONtechnologies released DEVONthink 2.9 with an entirely new sync engine. It’s like a brand new program and synchronization has been flawless. Although I’ve only been using the new version for a couple of months now, it feels better, faster, and deterministic in a way the older ones never did.

At this point, I’m cautiously optimistic that all of the problems I wrote about below are fixed and obsolete. My fingers are crossed!

I’m keeping this post up for historical reasons but I don’t think that it’s relevant anymore.

Q: I have DEVONthink Pro Office and I want to sync my home and work computers so that I can access documents in both locations. How can I do that?

A: You can’t. Give up. It won’t work reliably.

Q: No, really. How do I do that?

Longer A: Seriously, give up. It doesn’t work and you’ll just get angry and frustrated. Trust me.

I use and love DEVONthink Pro Office as a document manager. Pretty much every piece of information I come across goes into it, whether scans of utilities bills, PDFs of software manuals, Twitter messages I starred, or the complete collection of RFCs. If there’s any chance I might ever want to find something again, DTPO stores it. Its most important feature is the uncanny ability to return exactly the search results I want when I need to find something. Second only to that is its AI-powered “see also” feature: “you seem to be reading up on an obscure technical subject. You might also be interested in the author’s blog posts about it, some guy’s master’s thesis on the main algorithm, and the popular alternative version written by a teen living in a favela in São Paulo.”

It’s that good. And I’m still desperate to find anything else to replace it.

The main problem is that DTPO refuses - just flat-out digs its heels in and resists - syncing reliably for more than a few days at a time. The pattern always goes like this:

  • I start off optimistic, determined that this time will be different.
  • At home, I add a sync connection to Dropbox, or to my own WebDAV server which has been syncing OmniFocus and other apps successfully for years.
  • I sync one of my medium-sized (2GB or so) databases to that connection.
  • I select the Synchronize menu option and wait several hours as my data gets pushed up to the server.
  • At work, I set up the same connection and import the database. Then I select Synchronize and wait a few hours as all my data comes back from the cloud.
  • I use it for a couple of weeks until I start getting random sync errors that cause it to stop halfway through without copying across all my new documents.
  • After going through all the troubleshooting tips on their forum (of which there are many because this seems to happen to a lot of people), I give up and resign myself to the dreaded “Clean Location…” button which deletes all documents off the remote server.
  • I walk away from it for a few weeks so that I don’t throw my laptop out the window.

So I exaggerated a little. It is possible to reliably sync two machines running DTPO:

  • Pick one to be the primary machine.
  • Pick the other to be the secondary.
  • Do all your editing work on the primary. When you’re happy with it, use rsync or some other file copier to nuke what’s on the secondary and make it identical to the primary, losing any changes you might’ve made there.
  • If you’re at work and want to add a document, just email to yourself at home and import it into DTPO there later when you’d rather be playing with your kids, washing the dog, or doing anything else in the entire world.

That’s how you reliably sync DTPO. Anything else is just a ticking time bomb.