Arguably the most vital communication tool available to businesses of all sizes is email. It’s the platform-agnostic medium to convey thoughts, comments, and share the workload across groups far and wide.

While email’s death knell has been heralded for sometime now, the truth of the matter is that it’s still widely adopted and very much engrained in the day-to-day business functions, much the way hard copies were once created and filed to preserve the “data.”

Email is the modern day filing cabinet jam packed with all manner of attachments, notes, and other minutiae that help to move business forward and get the job done. But what happens when disaster strikes? When Apple Mail–which stores tens (or hundreds) of thousands of emails–suddenly doesn’t work anymore?

For those times when you’ve seemingly broken Apple Mail and there’s no hope in sight, the steps below–some extreme–may be the difference between getting Mail working again or not.

Note: The following troubleshooting steps are more focused on regaining access to Mail, not with data recovery of email messages. At the risk of sounding like a broken record, any data you rely on is worth having it backed up to (at least) another device regularly.

Reinitialize mail and configuration settings

Disclaimer: This will delete all mail and configurations from Apple Mail. System files will remain intact but all mail-related data will be destroyed.

  1. Quit Apple Mail
  2. Navigate to the following directory and delete the entire folder: ~/Library/Mail
  3. Empty the trash and launch Apple Mail to reconfigure the client with new mail accounts and settings

Factory reset Apple Mail and system settings

Disclaimer: This will delete all Mail app data and system-related data from OS X. All files, settings, and configurations will be destroyed, effectively rendering Apple Mail back to factory settings.

  1. Perform steps 1-2 above
  2. Navigate to the following directories and delete only the folders listed below:
    ~/Library/Containers/ Support/Mail
    ~/Library/Application Support/Address Book/MailRecents-V4.*
  3. Empty the trash and launch Apple Mail to reconfigure the client with fresh settings and new account configurations

Apple Mail is quite resilient. While the majority of end users will (thankfully) never have to encounter the odd behaviors that come with the mail database growing to 100+ GB sizes or those with dozens of accounts and over 100,00 messages, it can happen to any user on any Mac.

As always, the best defense against this or any major app or system meltdown is to have readily accessible backups of all your important data, especially email. Troubleshooting can help to get you back to work, but sometimes the only solution is to nuke the settings and go back to defaults.

How have you resolved problems with Apple Mail? Share your experience in the discussion thread below.