Microsoft to Retire OWA Light Client In Exchange Server

Microsoft plans to disable and remove OWA Light, the lightweight Outlook Web Access client for Exchange Server, in an upcoming update expected in August 2026. The company says retiring the two-decade-old legacy interface will reduce attack surface and engineering complexity, pushing users to the modern Outlook on the web experience instead. BleepingComputer reports: "OWA Light was an important compatibility experience when the web needed it. Today, the full Outlook on the web experience is the right place for us to focus," the Exchange Team said on Wednesday. "Retiring OWA Light will help reduce legacy surface area, simplify ongoing engineering work, and allow us to continue improving the experience customers use every day."

Microsoft introduced OWA Light roughly two decades ago as an alternative to OWA Premium, offering a simplified web interface for systems that didn't have Internet Explorer 6 or later installed or ran older web browsers. At the time, the company said that OWA Light offered a cleaner look, faster logon times on low-bandwidth Internet connections, and worked in locked-down browser modes (such as kiosks).

Microsoft deprecated OWA Light as of August 19, 2024, and announced this week that the OWA Light experience will likely be removed from Exchange Server (on-premises) next month. "In an upcoming Exchange Server update (estimated in August 2026), we plan to disable and remove the OWA Light experience. After that change is introduced, users will no longer be able to choose or be redirected to OWA Light and should use the modern Outlook on the web experience instead."

Re:

[korgitser]

My take is everyone who likes to talk about experience needs to be fired, and the software industry will be in a much better place.

Re:Experience

[sabbede]

They're called "the marketing department".

I suspect a great many things could be improved by their absence.

Re:

[korgitser]

Not only marketing. A pox on UX.

Re:

[radarskiy]

Why do you hate datasheets so much?

Re:

[sabbede]

I hate all sheets, that's why I sleep in a big pile of gravel.

Re:

[AuMatar]

Can we add "surprise and delight" to that list of firing reasons?

Re:Experience

[sabbede]

I think what happened is that over a decade ago, some market researchers found that millenials preferred "experiences" over physical items (probably because they make for better selfies). Marketing departments, being staffed with geniuses and definitely not people who are "like sheep, but drunk", ran with it and haven't let go.

Re:

[gtall]

So it should be "marketing experience", then. It has that sort ephemeral quality one knows as "marketing".

Re:

[sabbede]

As in "millennials preferred marketing experiences"? That would work with my assumption that they just wanted to do things they could post photos of. Self-marketing.

I forgot it existed

[jfdavis668]

Guess that would make it a good thing to retire.

Microsoft might be right about this one

[DarkOx]

As much as I want to say, it might be useful to have Web Based E-mail interface that will work in a basic / legacy browser, I don't know this is really true.

Not much of the web works at all if you try to use it with anything not Chromium or Apple-Webkit from less than five years ago. YMMV with recent Mozilla engines.

The few places where I can see someone maybe wanting to use this are the very places that people definitely should be isolating from all things Internet, especially not exposing it to e-mail content, which even if restricted to being from the local domain could still contain something malicious accidentally forwarded.

I can certainly understand why people would want / maybe just like or prefer a range of other legacy mail client. I mean if you handle a lot of mail and have been using Pegasus or something for the last 30 years and its all muscle memory, sure I get it. Moving from OWA-lite to OWA though probably isnt much bother for most people. At some point it makes sense to drop software likely very few folks are using.

Re:

[sabbede]

As you say that, I can't help but notice that this is a Microsoft story that didn't immediately spur a hundred knee-jerk, "M$ sux, use Linux" posts.

And here I thought that there was nothing MS could do that wouldn't create outrage. I guess deprecating something intended for IE4-5 compatibility is it.

Re:

[unrtst]

As you say that, I can't help but notice that this is a Microsoft story that didn't immediately spur a hundred knee-jerk, "M$ sux, use Linux" posts.

IMO, it's because OWA Light was a last resort, and the wrong one. For a Linux user that was looking for lightweight access, using a 3rd party email client over IMAP was the way to go. HOWEVER, Microsoft effectively killed that already.

One can technically access O365 mail from 3rd party clients, even making correct use of XOAUTH2 from ancient clients like Mutt and Pine (now "Alpine"). But that requires the domain admin to specifically allow those clients because the auth flow includes a client identifier - a

Re:

[thegarbz]

YMMV with recent Mozilla engines.

Aside from the occasional browser level bugs do you actually have an example of anything that doesn't work with a Mozilla engine? Even a 5 year old one? For all my complaints about Firefox (which are multitude) I keep hearing about parts of the internet that only work in Chromium based browsers, but I'm still keen to actually see a real example of this.

Firefox has it's problems, but I've yet to come across a single website that doesn't work on it or renders incorrectly on it. Can you share some? Or can we p

Re:

[slipped_bit]

My credit union pushed an update to its web site some months ago that caused it to no longer work with Firefox.

There's also a credit card company that won't let me sign in when they see I'm running Firefox on FreeBSD, but it's a superficial check on their end -- If I use a user agent switcher plug-in and make them think I'm using Edge on Windows it'll let me sign in with no problems.

When I run into a problem web site with Firefox I'll temporarily turn off uBlock Origin, but that almost never helps.

Re:

[DarkOx]

My banks site won't work in Firefox. Oddly it says it does, I have not tried on Windows. Maybe it would on Windows but I don't know why that should make a difference.

Re:

[markdavis]

Did you report it to your bank? It is almost certainly just a coding stupidity on their part, perhaps looking for a specific user agent.

Try: https://addons.mozilla.org/en-... [mozilla.org] and set it to lie to that domain about what you are using. I would absolutely leave my bank (or any service) for another one if I couldn't use Firefox... and they would know why as well, because I would have already reported it to them way before I left, and then would let them know why I left if it wasn't fixed.

In fact, I go to hun

The Web Experience?

[Fly Swatter]

Is that the web experience where 1/3 of the screen is advertisements, a pop-up asking you to subscribe every minute, or another persistent pop-up offering to give you assistance? Or maybe a complete takeover by a bad advertisement redirecting you to a phishing site? Or is it the one where each day a feature has disappeared?

Re:

[ulricr]

There are no ads; this is about Exchange server, not Hotmail.

Re:

[PPH]

How can I get 2/3 of my screen back? Asking for a frie..

Retool AI-generated apps that make it to production

Anyone Here?

[SlashbotAgent]

Is anyone here still running Exchange on-premise? I'm not bashing. Rather I'm genuinely curious what the current install base might be.

If you are still running Exchange on-premise, are you pure Exchange or an Exchange/M365 hybrid setup?

Re:

[EvilSS]

Yep. My company is still doing on-prem to 365 migrations on a regular basis and I'm aware of three companies that I've interacted with that are still on-prem including one that's staying on-prem only for the next few years at least. Personally getting rid of on-prem exchange (well mailboxes, until recently you needed to keep it for AD user mail attribute management) and sharepoint admin is one of the big upsides to going to 365.

Re:

[nuckfuts]

Is anyone here still running Exchange on-premise? I'm not bashing. Rather I'm genuinely curious what the current install base might be.

If you are still running Exchange on-premise, are you pure Exchange or an Exchange/M365 hybrid setup?

I'm currently working on migrating a couple of on-prem Exchange Servers, including one running Exchange Server 2010 on Windows SBS. The final straw was when the only supported version of Exchange switched to subscription-based licensing. If you're going to pay a subscription, it makes zero sense not to go with M365 and Exchange Online, and let someone else carry the burden of security patches and such.

Re: Anyone Here?

[Ilove_Noname]

There are plenty of reasons why staying on-prem may be required. Handling sensitive information being the main one. You have zero guarentees of what hands are in the cookie pot with the current legal landscape when you don't host your own data. Cloud Act/FISA court orders/etc. Sure it may be conaidered paranoia to a certain extent; however history has shown that there are levels of monitoring happening every day that we are just not aware of.

Re:Anyone Here?

[Hadlock]

Basically everyone who works in a regulated industry, or industry that should be does, yes.

Re:

[SlashbotAgent]

Are you such a person? If so, how do you handle what must be constant requests for 3rd Party App-\-M365 integrations that cannot be met by on-premise Exchange? Do you feel like you're missing out and being left behind?

Outlook is crap. Attitude is to Blame

[hydrodog]

I use Outlook on the web at a large university. Emails come in and DON'T SHOW. If I know they are there, I can search for them. This isn;t new; everything Microsoft does is shit. It doesn't work. To be fair, they obviously put more work in the native platform. But my experience with Microsoft, whether from a 200 page thesis in word that crashed every 5 minutes because there were equations and diagrams in it, to Word currently not formatting the same on Mac, Windows and Office 365, subtly corrupting papers w

Re:

[WCLPeter]

Then there's Excel, which I'm stuck using because work just loves their spreadsheets.

Where opening a 90mb file with some semi-complex calculations takes several minutes to recalculate after even the most basic change, drastically slowing down the machine. Where checking the "Processes" tab in Task Manager to see if there's a hung task eating all the resources and seeing Excel using 90% of the CPU and ELEVEN GIGS!!!!??? It's a 90mb file, it's the only one open, why the hell are you using 11gb??!!!

Frakking

comparison of mail servers

[johnjones]

so you want to get things done

you want freedom and do not want to compromise your ethics

run exim or https://en.wikipedia.org/wiki/Comparison_of_mail_servers

> https://en.wikipedia.org/wiki/Comparison_of_mail_servers [wikipedia.org]