Looking for solutions when you run out of space online.
It’s absolutely possible to transfer emails and attachments from Outlook.com (which counts against your OneDrive space), to your external hard drive. I’ll show you how.
The problem is that it’s generally not what you really want after all.
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Move email to an external hard drive
In most email programs, you can save individual messages as “.eml” files, which you can save wherever you like, including external hard drives. As an alternative, you can use an email program that allows for local folder storage, and move messages there. While not on your external hard drive, this approach allows you to access the messages from within the email program for easy access.
Microsoft recently changed the way email attachments in Outlook.com count against the amount of space you have available in your OneDrive cloud storage.
It’s a mess, and you can read about it here: Why is My Outlook.com Email Suddenly Full?
The result is that many people are looking for ways to free up space in Outlook.com and/or OneDrive. OneDrive is easy: if a file appears in the OneDrive folder on your machine, you can simply move it elsewhere, removing it from OneDrive, and the space will eventually be freed.1
Email is a different beast, because even though attachments count against your OneDrive storage limit, they don’t actually appear within OneDrive.
We’ll look at three solutions: downloading email and saving your emails and attachments to your hard disk; downloading email as .eml files and saving the attachments via the opened .eml file; or using a different email program that includes the capability to store folders locally.
The general solution is to download your email using a desktop email client and then save messages and attachments to disk wherever you like. Once you’ve done so (and backed up) you can safely delete the messages from Outlook.com and its Trash folder to free up the space.
Using the Mail program that comes with Windows 112 as our example, here you see I have a mail message with an attachment.
Click on the ellipsis (three dots) at the upper-right corner of the message to expose a dropdown menu of actions.
Click on Download.
Because the message has an attachment, you may get a warning.
Click on Keep.
You’ll now find a “.eml” file in your Downloads folder.
You can now copy or move this file to wherever you like, including an external hard disk. The file contains both the message and the attachment.3
Once you’ve copied the file elsewhere and backed up, you can safely delete the message from Outlook.com and then empty its “Deleted Items” or “Trash” folder to reclaim the space.
Using .eml files
By now you’re probably wondering what an .eml file is. The good news is that it’s an industry standard file format containing one complete email message.
To “use” it, just double-click on it in Windows File Explorer.
As I write this, there is a bug in the “new” Outlook email program that you may have been prompted to switch to. All of the examples above use this “new” Outlook because the transition to it seems inevitable. If double-clicking on a .eml file opens the calendar rather than the message, simply turn off the “new” Outlook.
This should open the .eml file in your default mail program and display its contents as an email message, including the ability to save the attachment separately.
Eml files are a great way to preserve and archive individual messages and store them wherever you like, including on your external hard drive.
But they can be a pain, since you need to download each separately, store each separately, and access each separately. That’s generally not what people are looking for (or expecting).
Using other programs
An alternative is to use a different email program that includes the capability to store folders locally. This can sometimes be more convenient, as it allows you to keep all of your email together using a single program, just organized into folders where some folders are stored only locally.
There are several programs that will do, but I’ll use Thunderbird, configured to access my outlook.com email address, as my example.
Local Folders, as the name implies, are folders that are stored locally, on your computer and nowhere else.
I’ve created a folder within my Local Folders called “My Personal Archive”. I can simply drag-and-drop the email message from my Inbox to this folder.
Here’s what that does:
- It downloads the message, including its attachment.
- It places that message in the My Personal Archive folder, which is only on my computer.
- It removes the file from my inbox and from Outlook.com.
You can do this for as many messages as you like, moving them all from Outlook.com online to the local folders stored only on your machine.
Local folder ramifications
There are two very important ramifications to using local folders.
First, messages in your local folders are stored only on your machine and nowhere else. This means you need to make sure your machine is backed up regularly, if it isn’t already, or you risk losing them if there’s a failure of some sort.
Second, external drives won’t work. Or, rather, I’d strongly discourage using one. First, all of your Thunderbird folders — local or otherwise — need to reside in the same place. Using an external drive would likely be much slower than on your internal hard disk, and accidentally running Thunderbird without the external drive connected would confuse the heck out of it, even after you reconnect the drive.
But overall, using a different email program with local folders is a fine solution to moving email messages from your online Outlook.com account to your PC. It’s just a lot of work.
Bonus: moving to a different account
A variation of the approach we just used to move email messages to a local folder can be used to move messages to a completely different email account.
For example, if we configure two email accounts in Thunderbird,4 then dragging and dropping an email message from your Outlook.com inbox to the inbox of a completely different email account will:
- Download the message from Outlook.com, including any attachments.
- Place that message in the inbox folder of the other account locally.
- Remove the file from the Outlook.com inbox.
- Upload the message to the inbox of the other account.
In other words, you’ve just moved the email message from one account to another. If that other account has more space available, this is also often a very reasonable solution to running out of space in Outlook.com/OneDrive.
If you’re impacted by the OneDrive/Outlook.com debacle, the approaches above are ways you can quickly free up space online and get on with your work without losing any of your important files or email.
Even if you’re not impacted, you now have some additional tools to help you manage your email, perhaps more flexibly.
Here’s some email worth managing: Subscribe to Confident Computing! Less frustration and more confidence, solutions, answers, and tips in your inbox every week.
Footnotes & References
1: You may need to empty trash online at OneDrive.com for the space to truly be made available.
2: Which is inexplicably called Outlook, not to be confused with the email program that comes with Microsoft Office, also called Outlook, not to be confused with the website at which you have your email account, which is outlook.com. Three different things all called Outlook.
3: In text format, no less. This means you can open this file using Notepad to see all the email headers and raw encoding of the email message.