How to Troubleshoot and Prevent Crashes

A crash is what happens when Postbox closes or quits unexpectedly. The cause of a crash could be any number of things. This article will help you fix crashes and show you how to get more help if you're having difficulties.

Update Postbox

The crash you're experiencing may have already been fixed in a new version! See Upgrading to a Newer Version of Postbox.

Update your operating system


  1. On the menu bar, open the Apple OS_Apple.png menu and select App Store.
  2. Select the Updates panel.
  3. If there are updates available, install them.

(Windows 10)

  1. Open the Start menu, select Settings.
  2. Open Update & Security.
  3. Click Check for updates.

Update your Internet Security software

Make sure you have the latest version of your Internet security software (including firewalls, antivirus programs, anti-spyware programs, and more).

Check if the crash happens in safe mode

Safe Mode is a special Postbox mode that can be used to troubleshoot and fix problems. Safe Mode temporarily resets some settings, and disables add-ons that might be causing problems.


Hold the Option key while launching Postbox (keeping it held until the window appears).


  1. From the Start menu search field, type in the following
    postbox.exe -safe-mode
  2. Press Enter.

Crash doesn't happen in Safe Mode

The cause is most likely caused by an add-on.

Crash still happens in Safe Mode

If your crash still happens in Safe Mode, it is not being caused by an add-on.

Re-install Postbox


  1. Delete Postbox from the Applications folder.
    NOTE: Your personal data is not being removed.
  2. Download and install the latest version of Postbox. See How to Install Postbox.


  1. Open the Windows Control Panel, and uninstall Postbox.
    NOTE: Your personal data is not being removed.
  2. Reboot your computer
  3. Delete the Postbox folder (if it exists) from the Program Files directory.
  4. Download and install the latest version of Postbox. See How to Install Postbox.

Create a new Postbox profile

Your Postbox profile is where Postbox stores your user data, such as your accounts, messages, and passwords. That data is stored in a separate location from the Postbox application. As a troubleshooting step, see if Postbox crashes in a new profile.

  1. On the menu bar, go to Help > Troubleshooting.
  2. In the Postbox Troubleshooting window, select Open Profile Manager on Restart.
  3. Click Apply and Restart.
  4. Click Create Profile.
  5. Click Continue.
  6. Name your new profile, and click Done.
  7. With your new profile selected, click Start Postbox.

If your new profile is not crashing, see How to Migrate Essential Data to a New Profile.