Written by Jennifer Walsh. Reviewed for technical accuracy by Shubham Dixit, Independent Expert in Email Forensics and Data File Conversion.
Shubham is an independent external reviewer and not an employee of PCDOTS.
Quick answer. Moving a PST to the cloud means one of two things. You can store the PST file itself in cloud storage such as OneDrive, Google Drive or iCloud Drive as a backup, or move the mail inside it into a cloud mailbox like Gmail, Outlook.com or iCloud Mail over IMAP so it is readable everywhere. This guide covers both, and which one to pick.
On this page
Two things “to the cloud” can mean
Before you move anything, it helps to know that moving a PST file to the cloud splits into two quite different jobs, and people often want one while reading about the other.
The first is putting the PST file into cloud storage, such as OneDrive, Google Drive or iCloud Drive, as a backup. That is fast, but the result is just a file sitting in the cloud, you cannot open it as mail in a browser. The second is moving the mail inside the PST into a cloud mailbox, such as Gmail, Outlook.com or iCloud Mail, over IMAP, so the messages are readable in webmail and on every device. Decide which you want, because the steps are nothing alike.
Same phrase, two different jobs. Pick the one you actually need.
“The confusion here is real and it costs people time. Dropping a PST into a cloud drive feels like you have moved it to the cloud, and you have, but only as a file, you still cannot open it in the webmail. If what you want is the mail readable in the cloud, that is an IMAP job, you push the messages into the mailbox. The other thing I always warn about is letting a PST sync while Outlook still has it open, that is a good way to corrupt it. Close Outlook first.” Shubham Dixit, Data Migration reviewer (draft, pending approval)
The file into cloud storage
If all you want is a safe copy of the PST off your machine, this is the quick route, and it works the same for OneDrive, Google Drive, Dropbox or iCloud Drive. You are simply placing the file in a synced folder.
Close Outlook first. Outlook locks the active PST while it is open, so quit Outlook completely before you touch the file. This is the step that prevents most problems.
Copy the PST into your cloud folder. Find your .pst file, usually under Documents, Outlook Files, and copy it into your OneDrive, Google Drive, Dropbox or iCloud Drive folder. Let it finish uploading before you reopen Outlook.
Two honest cautions. A PST is often several gigabytes, so it can eat into your cloud storage and take a while. And this is a backup only, the file sits in the drive, you cannot read those emails in the webmail or on your phone from it. For that, you need the next section.
The file-backup route is quick, but mind these four things.
The mail into a cloud mailbox
If you want the messages themselves in the cloud, readable in Gmail, Outlook.com or iCloud Mail and on your phone, you move the mail over IMAP. A cloud mailbox cannot take a PST directly, so a client bridges it.
Open the PST and add the cloud mailbox. In Outlook, open the PST with File, Open, Open Outlook Data File, then add your cloud account as an IMAP account. It appears in the sidebar alongside the PST.
Drag the mail up. Select the messages in the PST and drag them into a folder under the cloud account. Because it is IMAP, they upload to the cloud as you drop them and appear in the webmail shortly after, attachments included.
Two things to know per cloud. iCloud Mail uses the server imap.mail.me.com, and on a Mac without Outlook you can convert the PST to MBOX and import it through Apple Mail instead, our guides to move Outlook PST to Apple Mail and import MBOX to iCloud cover that. And the sign-in is not a plain password any more, which is the next section.
The sign-in changes per cloud
This is the detail that quietly blocks the mailbox route. Most clouds no longer accept your normal password from a mail client, so check the right sign-in before you start.
Gmail and iCloud need an app-specific password, generated in your Google or Apple account security settings, used in place of your normal password. Outlook.com uses a modern Microsoft sign-in, a sign-in window rather than a typed password. Get the right one ready and the client connects on the first try.
Moving the mail in bulk, a tool
The manual mail route means dragging messages by hand, which is slow for a large PST, and it needs Outlook. For the mailbox job specifically, a converter uploads the PST’s mail straight to a cloud account over IMAP, no Outlook required. The PCDOTS PST Converter reads a PST, including an orphaned one with no Outlook behind it, and sends the mail into Gmail, Outlook.com, iCloud or another cloud mailbox in bulk, with attachments. It runs on Windows and uses the same app-specific password or sign-in the manual route does. This is for the mail-into-a-mailbox job, if you only want the file backed up, no tool is needed, just copy it to your cloud drive. A free version uploads the first ten items per folder so you can test it.
The tool route, for the mail-into-a-mailbox job.
Here are the steps with the screens.
Step 1. Install and run the converter on Windows, then open the menu.
Step 2. Choose Email Data Files, Outlook PST, and add your files.
Step 3. Open the Export menu and select IMAP.
Step 4. Enter your cloud address and app-specific password, then Save to upload.
For a specific mailbox, see our guides to import PST to a Gmail account and move Outlook PST to Apple Mail.
The methods compared
Match the route to which of the two jobs you actually want.
| Method | Best for | Good to know |
|---|---|---|
| Copy PST to a cloud drive | A backup of the file, free | Close Outlook, not readable as mail |
| Outlook plus cloud IMAP | Mail into a mailbox, free | App password or sign-in, drag by hand |
| PST Converter tool | Bulk mail, or orphaned PST | Windows, uploads over IMAP |
Frequently asked questions
How do I move a PST file to the cloud?
Two ways. Copy the PST into a cloud drive like OneDrive or iCloud Drive to store the file as a backup, or move the mail inside it into a cloud mailbox over IMAP so it is readable. They are different jobs.
If I put my PST in a cloud drive, can I read the emails in the webmail?
No. In a drive it is just a stored file. To read the messages in the webmail you have to move the mail into the mailbox over IMAP.
Which cloud storage can I use for the file?
Any of them, OneDrive, Google Drive, Dropbox or iCloud Drive. Close Outlook first, then copy the .pst into the synced folder and let it upload.
Why will the cloud not accept my password in Outlook?
Most clouds need more than a plain password now. Gmail and iCloud use an app-specific password, and Outlook.com uses a modern Microsoft sign-in. Set that up before adding the account.
Should I close Outlook before copying the PST?
Yes. Outlook locks the active PST while open, and letting a live PST sync to the cloud can corrupt it. Quit Outlook, then copy the file.
Can I move a very large or orphaned PST?
For the mail, a converter reads large or orphaned PST files and uploads them over IMAP in bulk. For the file itself, size only matters for your cloud storage limit.
Decide what you mean by to the cloud
So make the call before you start, because it saves the whole headache. If you want a safe copy of the file, close Outlook and drop the PST into OneDrive, iCloud Drive or any cloud drive, and you are done, just remember you cannot read it as mail there. If you want the messages living in a cloud mailbox, get the right sign-in, add the account to Outlook over IMAP, and drag the mail across, or let the converter push a large PST up for you. Pick the job that matches what you are really after, and move it once, the right way.
