Be careful when moving or copying email with Apple Mail, Outlook, Thunderbird or Other Software

There are times when you will want to move or copy email messages from an email account to another email account or to local folders on your computer. To do this, you will want to use an email client such as Apple Mail, Outlook, or Thunderbird.

While the process usually works, there are some situations where you may lose email attachments after the messages are transferred.

The precise steps to copy or move messages will differ depending on what software you use and whether you are using a Windows or Apple computer.

Process Suggestions

Here are some general steps and precautions that should apply to whatever situation you are in.

1. LOCAL FOLDERS. Most email clients will have some method for creating local folders for storing emails. If you delete an email account, the messages stored locally should remain and can be backed up to an external hard drive. You will want to use the local folders option to eventually make a backup of your emails and possibly copy them to another system.
   • In Outlook on a Windows computer, you would need to create a dedicated PST file and put your emails in folders store in that file.
   • In Thunderbird, there is an option to create local folders.
   • In Apple Mail there is an option to create “On My Mac” folders.
2. COPY MESSAGES. It is important that you copy messages to a local folder rather than moving them.
   • If you use the move feature, messages can appear to have been transferred to the new location, and removed from the new location, but the process could still be running in the background and then you won’t know when the process is complete.
   • It is important to copy files in smaller batches. If you choose to copy many hundreds or thousands of emails, the software may cause a delay that causes the copy process to stop with an error message “timed out error.”
   • Depending on the speed of your computer, working with smaller batches can help you ensure that the process is working smoothly.
   • Keep a journal as you work. Make a notation of what folders and messages have been copied. If you have many folders on the email service, you will need to recreated these on your local folder system.
3. CHECK MESSAGES. After copying message to your local folders, review all the messages to ensure that attachments are present and can be opened.

Additional Considerations

• NEW EMAIL SERVICE. If you intend to eventually move your email messages to another service, you can copy them back from your local folders to the new service.
• BEFORE DELETING. When deleting emails from an email service for the purpose of freeing up space, always check to make sure you have a local working backup before deleting from the service.
• EMAIL MANAGEMENT. A fast and reliable system for managing the administration of emails would be Thunderbird running on a powerful Windows computer. This is a helpful tool even if your primary computer is an Apple computer. Thunderbird provides a detailed progress window, whereas Apple Mail and Outlook only provide general progress information. You can use Thunderbird as your system for large-scale copying, moving, and backing up even if it’s not your daily use email client.
• SECURITY. One reason for moving emails off services like Google, Yahoo, AOL, and Microsoft, is security. If an account ever gets hacked, you want to minimize your exposure. Consider retaining 1-2 years of emails in the cloud. Store everything else locally, and have it backed up.
• BACKUPS. Consider making a backup copy of your emails to a local folder every few months just in case something goes wrong with your account or provider’s service.