Your Outlook Looks Different: New Outlook vs Classic Outlook, and How to Switch Back

One morning the email program looks different. The layout is flatter, the ribbon is shorter, half the buttons have moved, the folder list has changed colour, and somewhere in the corner there is a toggle switch that was not there before. Nothing is broken, nothing has been deleted, and you have not been hacked. What has happened is that Windows now ships two entirely different programs that are both called Outlook, and yours has changed from one to the other.

This causes more confusion than almost anything else we get asked about, for a simple reason: nearly every set of Outlook instructions on the internet was written for one of the two and does not say which. You follow the steps, the menu the article describes does not exist on your screen, and you conclude that something is wrong with your computer. It is not. This guide sorts out which one you are looking at, how to go back if you want to, what you genuinely lose either way, and one thing about the new one that is worth knowing before you add a work mailbox to it.

First, ten seconds to work out which one you have

Microsoft's own test is the quickest. Look at the top right corner of the Outlook window. If there is a Settings button up there, you are in the new Outlook. If there is no Settings button in the corner, and instead there is a File tab at the top left and a Send/Receive tab along the ribbon, you are in classic Outlook. Microsoft puts it plainly: "If you have the Settings button, you have the new Outlook. If the Settings button is missing, you're using classic Outlook."

The Start menu will tell you as well. Press the Windows key, start typing Outlook, and look at the names in the results. The older program is listed as "Outlook (classic)" in the app list. If the only Outlook in the list has no such tag, and you have never had a paid Office suite on this machine, then the new Outlook is the only one you have ever had.

One more difference that matters if you are following instructions from elsewhere: classic Outlook keeps your mail in a local data file on the PC, has a File tab, uses mail profiles, and can load plug-ins from other programs. The new Outlook does none of those things. That single fact explains almost every set of steps that does not match your screen.

Why yours changed without anyone asking you

There are three ordinary routes to this, and none of them is a fault.

The first is Windows Mail. The simple mail app that came free with Windows 10 and early Windows 11 is gone: Microsoft states that "Support for Windows Mail, Calendar, and People ended on December 31, 2024" and that those apps can no longer send and receive. Everyone who was using Mail was pushed to the new Outlook, which is now the free mail app built into Windows.

The second is a new computer. Microsoft's own support page is blunt about it: "Starting in 2024, many new devices are preinstalled with new Outlook for Windows and the classic Outlook app isn't included." If you replaced a machine recently and the email looks unfamiliar, this is almost certainly why. Your old PC had classic Outlook because an Office suite put it there; the new PC came with the free built-in one instead.

The third is the toggle. Classic Outlook has carried a "Try the new Outlook" switch in its top right corner for a while now, and it is easy to knock on by accident. Once it is on it does not just open the new app once. In Microsoft's words: "While the toggle is turned on, if you try to launch classic Outlook for Windows or Windows Mail you'll be automatically redirected to new Outlook for Windows." So it looks permanent, and people assume an update took the old one away. It did not.

How to switch back to classic Outlook

If the toggle is what moved you, the toggle moves you back. In the new Outlook, find the switch at the top right and click it. Microsoft documents two choices at that point, and the difference between them catches people out.

"Switch back to classic Outlook" is the permanent one: it asks you for feedback on why you are leaving, and from then on launching Outlook opens the classic app again. "Use classic Outlook this time" opens the old app for this session only, without changing the setting, which Microsoft describes as a good way "to quickly get to classic Outlook for comparing the apps or completing any specific workflows". If you pick the second one and then wonder why you are back in the new Outlook tomorrow, that is why.

If there is no toggle at all, there are two likely reasons. Microsoft's first is the obvious one: "You may not see the toggle if classic Outlook for Windows isn't installed on your device." You cannot switch back to a program that was never there, which is the situation on most new home PCs. The second applies to work accounts, where an administrator can switch the toggle off for the whole organisation.

There is also a documented fallback for when classic Outlook is installed but the toggle is missing or stuck. Microsoft's own instructions are to open Registry Editor from the Start menu, go to Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Outlook\Preferences, double-click UseNewOutlook at the bottom of the list, set the value to 0, and then start classic Outlook from the Start menu. That is a first-party instruction, not a hack off a forum. It is still the registry, though, so if you are not comfortable in there, this is a reasonable thing to hand to someone else — a mistyped value in the wrong key is a bad afternoon.

One last tip from the same page, and it is the one that solves it most often in practice: launch classic Outlook from the Windows Start menu rather than from inside the new Outlook, and pick the icon that does not have a New tag on it.

You probably do not have to choose

This gets missed because the toggle makes it feel like a one-way door. It is not. Microsoft supports running both at the same time and says so directly: "Microsoft will maintain the ability to run both classic and new Outlook side-by-side, so that you can learn the new Outlook while staying productive."

The practical setup takes a minute. Toggle back to classic, then pin both apps: press the Windows key, type Outlook, right-click each of the two entries in turn — the plain one and the one tagged classic — and choose Pin to taskbar. Now you have two icons, they open two separate programs, and you can do the job that only classic can do in classic while using the new one for everyday mail.

For most people who are on the fence, this is the right answer for the next year or two. You are not migrating; you are keeping a spare key.

What classic Outlook still does that the new one does not

Microsoft publishes a feature-by-feature comparison of the two, and it is far more candid than you would expect — it marks features as available, partially available, not supported, or upcoming. The version we checked for this article carries the note "Last updated: September 23, 2026", so this is a moving target and the gaps have been closing steadily. As of that date, here is what is genuinely missing rather than merely moved.

Marked not supported in the new Outlook: COM add-ins, VBA macros, custom forms, the Outlook Object Model used by other programs to drive Outlook, importing and exporting a set of rules, and — a real one for small offices — opening files from a network share. Marked upcoming, meaning not there yet: multiple mail profiles, which is how classic Outlook keeps two completely separate sets of accounts apart.

Marked partially available, which usually means the feature exists but in a thinner form: rules, Quick Steps, search folders, mail merge, public folders, offline support, delegate access to a shared mailbox, and support for Outlook data files. On that last one Microsoft's own note reads: "New Outlook supports importing mail, calendar events, contacts, and tasks, along with broader export and file-management capabilities. Some classic Outlook capabilities remain unavailable." In plain terms: the new Outlook can take mail in from a .pst file, but it does not live in one the way classic does.

It is only fair to run the list the other way too, because a few things are better. Pinning a message to the top of the inbox, snoozing a message so it comes back later, Sweep for bulk-clearing a sender, folder colors and category favorites are all listed as not supported in classic and available in the new one. The unified view across several accounts is genuinely nicer, and it is free with Windows.

And one correction, because it is repeated all over the internet and it is wrong: POP accounts. A great deal of advice says the new Outlook cannot handle a POP mailbox. Microsoft's comparison table lists POP as available in both classic and new Outlook. If you have an old POP account from an internet provider or a web host, that alone is not a reason to stay on classic.

The add-in question is the one that actually decides it for a business

If you run a small business, ignore everything above and check this one thing first. Microsoft is unambiguous: "In new Outlook for Windows, COM add-ins aren't supported."

A COM add-in is the kind of plug-in that installs itself into classic Outlook from another program on the same PC. If your Outlook has an extra tab or toolbar button put there by a practice-management system, a CRM, an accounting package, a document-management or PDF tool, a dictation package, a scanner or fax utility, or an old line-of-business program from a vendor who has not updated it in years, that is almost certainly a COM add-in, and it will simply not be there in the new Outlook. Not broken, not hidden — absent.

The newer style of plug-in, which Microsoft calls a web add-in, does work in the new Outlook. The awkward part is that you cannot tell which kind you have by looking at it. The quick check: in classic Outlook go to File, then Options, then Add-ins, and read the list at the bottom under COM Add-ins. Anything in there is something you would lose. If that list is empty or only holds things you have never knowingly used, the new Outlook is a much easier move than you think.

There is a second business-shaped gap worth naming beside it. On-premises Exchange — a mail server sitting in your own office — is listed as only partially available in the new Outlook, supported through IMAP with functionality limited by what that protocol can do. If your mail comes off a server in the back room rather than from Microsoft 365, test carefully before you move anyone.

The part nobody mentions: where your mail actually lives now

This is the detail we think most people would want to be told, and almost nobody is. If you add a non-Microsoft account — a Gmail or a Yahoo address — to the new Outlook for Windows, your mail is not simply fetched to your PC the way classic Outlook fetched it. Microsoft's own explanation: "Syncing your account to the Microsoft Cloud means that a copy of your email, calendar, and contacts will be synchronized between your email provider and Microsoft data centers."

That is how the new Outlook can offer search, Focused Inbox, pinning, snoozing and package tracking on a Gmail account — the features run against Microsoft's copy, not against Google's. Microsoft also states that your experience inside Gmail itself is unchanged, and that both Microsoft's terms and your own provider's terms continue to apply to the data.

None of that is a scandal, and it is not a reason to panic. It is a reason to make a deliberate decision rather than an accidental one. If the mailbox is a personal Gmail account, most people will not mind. If it is a business mailbox holding client records, medical information, or anything covered by a confidentiality agreement or a professional obligation, the fact that a second company now holds a synchronised copy is something you should know before you click through the setup, not after. Classic Outlook talking straight to your provider does not do this.

If your PC came with the new one and you want classic anyway

This is the most common version of the question we get from people with a brand-new computer, and it has a specific symptom. You find an Outlook icon, click it, and get an error that opens "We couldn't verify and install this because it is not available in the Microsoft Store." and then tells you to download it from the publisher's website instead. That is not a broken installation. It is the shortcut for a program that was never put on the machine.

Microsoft publishes a page for exactly this, titled "Install or reinstall classic Outlook on a Windows PC", with a language picker and a direct download. The honest caveat is the licensing one: classic Outlook is a paid desktop application. As Microsoft's version page puts it, "The classic Outlook app is included with many Microsoft 365 subscriptions that include the desktop apps, and versions of Office such as Office Home & Business." If you have one of those, you are entitled to classic Outlook and it is worth installing. If your household has never had a paid Office, the new Outlook is what you have, and the switch-back advice above does not apply to you.

Is classic Outlook being killed off, then?

Eventually, but not this year, and the schedule is published rather than rumoured. Microsoft describes three stages. In the opt-in stage, which its migration page still described at the time of writing, "New Outlook is off by default" and classic users see the try-it toggle. In the opt-out stage new Outlook becomes the default but, in Microsoft's words, "Users can still revert to classic Outlook during this stage if needed." Only in the third stage does the door shut: "In the cutover stage, users won't be able to switch back to classic Outlook."

Two commitments sit underneath that and they are the ones worth remembering. Microsoft says it will give at least twelve months of notice before moving production users into each of the later stages. And on the long stop it is explicit: "Existing installations of classic Outlook through perpetual and subscription licensing will continue to be supported until at least 2029." Its own announcement adds that the cutover stage "does not signify the end of support for classic Outlook for Windows".

So if someone has told you that classic Outlook is being switched off imminently and you need to pay someone to migrate you this month, that is not what Microsoft's documentation says. There is no consumer deadline published for the later stages, the support floor is 2029, and the toggle still works today.

Before anyone uninstalls classic Outlook, deal with the data file

Here is where this stops being about menus and starts being about losing things. Classic Outlook stores mail in a local data file on the PC — a .pst or .ost. If your account is a POP account, that local file may be the only copy of years of mail in existence: POP downloads messages to the computer and, depending on the settings, may not leave them on the server at all.

The new Outlook does not work that way, and remember that Outlook data file support is only partially available in it. So the order of operations matters. Before you uninstall classic Outlook, before you wipe an old PC, and before you accept a helpful offer to "clean up" the old machine: get that mail somewhere safe. In classic Outlook, File, then Open & Export, then Import/Export, then Export to a file, and save the .pst somewhere that is backed up. Then, and only then, let the old program go.

The same warning applies to a new computer. If the old PC had classic Outlook and the new one does not, nothing about the transfer will move that mail for you automatically. It is the single most common way we see decades of email quietly vanish — not through a crash, but through a tidy-up.

So which one should you use?

For most home users: the new Outlook is fine, and if it is already what you have, there is no good reason to fight it. It is free, it is maintained, it handles Gmail and Yahoo and iCloud and POP and IMAP, and the things it does better — pinning, snoozing, one view across several accounts — are the things home users actually use. Give it a fortnight before you judge the layout.

Stay on classic, for now, if any of these are true: Outlook has plug-in toolbars from other business programs; your mail comes from an Exchange server in your own office; you depend on separate mail profiles, complex rules you cannot face rebuilding, or public folders; or you have a large .pst archive you work out of daily. In those cases the honest advice is not to migrate on someone else's schedule. Pin both, use classic for the work that needs it, and revisit in a year, because the gaps really are closing.

And whichever one you land on, the deciding factor is not the ribbon. It is whether your mail exists somewhere other than this computer.

How we can help

We do this one a lot, and most of it is quick. We can tell you in a minute which Outlook you are actually in, switch you back to classic safely if that is the right call — including the registry fallback when the toggle has gone missing — and set both up side by side so you are not gambling on it. For a business, we can go through the COM add-in list before anything changes and tell you plainly what would stop working.

We can also do the part that matters most: get your old mail out of a .pst and into a backup before an old PC is retired or wiped, move an account from POP to IMAP so your mail is no longer trapped on one machine, and set up a mailbox on a new computer so the archive comes with it. If your email has started looking strange and you would rather someone just looked at it, that is a short job and we are happy to do it.