Outlook Folder Types POP3 IMAP Exchange PST and OST and How to Backup and Move them to a New PC

Classic Outlook supports a variety folder/data file types, which are useful for different purposes. As of 2023, New Outlook is now available. New Outlook does not support most of the folder/data types that Classic Outlook does and only supports Exchange accounts. New Outlook lacks many features compared to Classic Outlook.

Classic Outlook vs New Outlook

Classic Outlook and New Outlook are very different and work differently. We have an extensive guide covering the differences here: New Outlook vs Classic Outlook vs Outlook for Windows

The differences are easier to see, since they are not well labeled. The easiest way to tell is to look in the upper left hand corner and see if there is a File option/button. If the File option exists, then it is Classic Outlook, if not, it is New Outlook.

On the left hand side, we have Classic Outlook and on the right hand side we have New Outlook.

Main Differences between Classic Outlook and New Outlook

New Outlook is free, Classic Outlook requires an Office license.
New Outlook does not support PST or OST files. This means you cannot bring your data from Classic Outlook into New Outlook unless that data is on an Exchange account.
POP email addresses are not supported in New Outlook.
COM Add-ins are not available in New Outlook.
New Outlook does not work offline, the app won't launch if you do not have internet

If you want to turn off New Outlook and switch to Classic Outlook, you can use this guide.

PST vs OST Data Files

New Outlook does not support PST or OST files. This means you cannot bring your data from Classic Outlook into New Outlook unless that data is on an Exchange account.

For more information, check out the Microsoft guide here.

PST

A PST file is essentially an offline copy of all the data you have in Outlook. These can be transferred to other computers or simply stored as backups. This data is not backed up on any cloud account, so mailbox limits do not apply to contacts, calendar, etc. Mailbox limits still apply to emails though.

OST

An OST file is similar to a PST file however an OST file is synchronized with a cloud account such as an Exchange account. These can be backed up similar to a PST file, but are subject to mailbox limits on the cloud account. The cloud account is typically an Exchange account but this is not always the case.

IMAP vs POP3 vs Exchange

New Outlook does not support POP3 or IMAP folders. This means you cannot bring your data from Classic Outlook into New Outlook unless that data is on an Exchange account.

For more information, check out the Microsoft guide here.

IMAP

IMAP is the most common folder type. IMAP does not have any way to sync contacts or calendar to anywhere. The data simply lives on the PC only.

POP3

POP3 is a very old standard and should not be used if possible. POP does not allow you to use more than one computer at once for email. POP does not have any way to sync contacts or calendar to anywhere. The data simply lives on the PC only.

Exchange

Exchange is a very modern folder type. Unlike IMAP, Exchange supports categories correctly. Exchange will sync to any other computer as well as the Outlook mobile phone app.

How to Sync IMAP and POP3 Folders to a phone or other PC

CompanionLink is a powerful way to sync Outlook data to your phone or to another PC. We offer a variety of sync methods, check one of our Setup Guides to get CompanionLink reconfigured to sync with your mobile device.

Android Phone or Tablet

iPhone or iPad

How to Install Classic Outlook for Windows

Watch this video to see how install Classic Outlook.

If you only have access to "New" Outlook or the free newly branded New Outlook (Formerly Windows Mail), you can install the Classic version of Office from Microsoft's Website.

There are 2 types of installers, online and offline. The online installer is easier and usually works, but not always, when the online installer does not install Classic Outlook, you must use the offline installer.

Online Installer (Easiest method)

Click Here to download the Classic Outlook online Installer.
Follow the Install Prompts
Connect Your Email Accounts
Setup CompanionLink.

Note: If this does not install Classic Outlook, you must use the offline installer:

Offline Installer (Most Reliable)

Click Here to download the Classic Outlook offline Installer.
Right click the IMG file > Mount
Click Open if prompted
In the mounted directory, Go to the Office Folder and run Setup64.exe
Follow the Install Prompts
Connect Your Email Accounts
Setup CompanionLink.

Setup Help or Advanced Configuration on the New PC

If you want us to set it up for you or you use an advanced configuration such as unique field mapping, multiple sync, multiple data sources, or custom sync filters we would recommend our Setup Service. There are two options here.

Option 1 - RunStart: A RunStart is a one time Setup, this lets us login to the machine, install CompanionLink for you and walk through any custom settings you might need. Click Here for more info on RunStarts.

Option 2 - Premium Support: Premium Support offers one year of continued support which includes installing and setting up CompanionLink for you. Click Here for more info on Premium Support.