OCR causes DTP to hang every few weeks

I have a recurring problem with Devonthink Pro Office 2.3.5. (it may have occurred with previous updates as well). Every few weeks, the OCR process will hang while reading a scanned PDF. When this happens, I’ve still been able to continue working with other parts of DTP most of the time (I don’t want to be too exact about this because I don’t always try out the rest of the application, my usual first reaction is to force-quit the app).

Once the problem begins, OCR will not work at all without freezing.

As a result, I am uninstalling and reinstalling DTP every few weeks.

Does anyone have any suggestions as to what specific file (possibly a cache or plist file somewhere??) might be the culprit? I would much rather delete one or two plist files than reinstall everything.


My first thought is when DTP hangs…

  1. Open /Applications/Utilities/Activity Monitor.
  2. Select DEVONthink Pro and press the “Sample Process” button.
  3. Save this report and submit it to the DEVONtechnologies bug tracking system

Please forgive what may be a dumb question: how often do you restart your Mac or log out and log in again?

Are there any entries in your logs that reference the hangups?

I have noticed that OCR is painfully slow and processor-intensive. Perhaps it is just more painfully slow on your machine?

At the first indication that a gremlin has set up housekeeping in a computer, I recommend a restart. That will clear RAM, freshly reload the operating system and applications and documents.

That may fix glitches resulting from running out of free RAM, memory errors (“cobwebs” accumulating), a stuck cache or process, a cosmic ray zapping RAM and twiddling bits, etc. Apple’s operating system and hardware reliability is as good as it gets at consumer prices. But we couldn’t afford them if Apple made them completely error-correcting and fault tolerant.

Then run Tools > Verify on each of your DEVONthink databases, to check for possible errors. If errors are found, revert to an earlier state of the database (Tools > Restore Backup, followed by Verify & Repair to attempt to return to an error-free state of the database, or Rebuild the database, or replace the database with an external backup.

You do make backups of your databases that are stored on an external medium, right? If not, you need to think about all the Bad Things that could go wrong, starting with (but not stopping at) a hard disk failure. Could your important data survive loss or theft of all your computer equipment, a fire, a flood? I keep database archives on a portable hard drive stored in a safety deposit box at my bank, and periodically update the database archives. My backup strategy is redundant and includes use of Apple’s free Time Machine app.