Communication error


Mac OS 10.9 Mavericks users have reported frequent connection issues. The following error messages may appear as a symptom:

Communication with the host was interrupted and could not be re-established. All affected windows will be closed.


Client no longer responding. Connection closed. (Error 51)

Mavericks includes a feature called “App Nap” that can power down apps when you they’re not in use to conserve battery life. For most apps this is fine, but for FileMaker it can cause issues.

The FileMaker Pro client sends a message to the server/host if there is no network activity for 60 seconds.  If the server/host doesn’t hear from the FileMaker Pro client twice (after 120 seconds), then it will disconnect the client.

We’ve fixed the issue by disabling the “App Nap” feature for FileMaker. Here’s how:

  1. Open the Applications folder. From the Go menu in the Finder, choose Applications.
  2. Find the FileMaker 13 folder and open it.
  3. Click once on the FileMaker 13 app. From File menu choose Get Info or press Command-I.
  4. Check the Prevent App Nap option and close the Get Info window.


If the problem continues follow these additional steps:

  1. Open up your System Preferences window. You can do this by selecting the apple icon on the top left hand side of your screen and selecting System Preferences.
  2. Once this is open, click on the Energy Saver icon.
  3. Towards the bottom of this screen you may see a Lock, simply click on this and enter in your administrator details to make the changes.
  4. On the Computer sleep slider, drag the toggle to the very right above ’Never’. 
  5. Please also ensure that the ‘Put hard disks to sleep when possible’ checkbox is NOT selected.
  6. Once you have completed both points 4 & 5, ensure you then select the lock icon so that no further changes can be made.

Energy Saver

Have more questions? Submit a request
Powered by Zendesk