Microsoft 365 organisational theme no longer applied in New Outlook and Outlook on the web

Question

Microsoft 365 organisational theme no longer applied in New Outlook and Outlook on the web

Nirmal Philips Tom 65

We have a Microsoft 365 organisational theme configured through the Microsoft 365 Admin Center, including our company logo and custom navigation bar colour.

Until recently this branding was displayed correctly in New Outlook for Windows and Outlook on the web.

We have now noticed that multiple users are seeing the standard blue Outlook header instead. The organisational logo is also no longer displayed.

The organisational theme itself appears to be working correctly elsewhere — for example, SharePoint continues to display our company logo and custom navigation colour correctly. We have also verified that the Default Theme configuration in Microsoft 365 Admin Center remains correct.

The issue occurs in both:

New Outlook for Windows
Outlook on the web

Restarting New Outlook does not resolve it, so this does not appear to be a local client issue.

Has anyone else noticed this recently? Is there a current Outlook rollout/change affecting Microsoft 365 organisational themes, or is this a known issue?

Dan Cauchois 10 Reputation points

2026-08-26T10:37:38.62+00:00

We are seeing the exact same issue.
NolanSayCat 5 Reputation points

2026-08-27T10:01:35.5166667+00:00

So, can someone explain the point of allowing admins to define org themes via admin centre, if the new "experience" is being designed to completely ignore it??
Olivier Lagacé - VNET 5 Reputation points

2026-08-28T14:15:03.97+00:00

This is ridiculous. We’re an MSP, and many of our clients are calling us because they think they’ve been hacked. Using custom organizational colors is one of the things that helps users distinguish their legitimate tenant from a phishing site.

How could you take such a major step backward?
Nicholas Piasecki 6 Reputation points

2026-08-31T17:33:56.7966667+00:00

Restarted today and hit this. It worked for years and was very helpful to tell which tenant I was in. Considering the amount of other users who are experiencing the issue, it's safe to say that they broke it. Hopefully a Fortune 500 will eventually complain and it'll just magically fix itself one day.
Jayden Cameron 0 Reputation points

2026-09-02T07:34:42.3833333+00:00

Confirming the same issue in our CamCore tenant.

This worked normally until about a week ago, with no changes to our tenant theme. The default theme still has our organisation logo configured and “Prevent users from overriding their theme” enabled. SharePoint and OneDrive continue to show CamCore branding, but Outlook on the web now shows the standard blue Outlook header with no organisation logo.

The timing appears to align with MC1458476. In Outlook Settings → General → Appearance, the built-in/classic themes are present, but the locked organisation theme is not applied. Has Microsoft confirmed whether this rollout changes support for organisation themes in Outlook, and is there a fix or rollback ETA?
Technonath 10 Reputation points

2026-09-02T10:40:24.98+00:00

As per normal the usual lack of testing on the developers part and complete lack of any communication between the "support team" and the dev team. MS Support is a total joke, it is just a bunch of people working for an external company branded as MS Support and as soon as any ticket needs escalation to a dev they have no powers or channels to do this.

Don't expect an answer from the support team - it will never come.

Microsoft employees work in such small Silo's now with no communication between the teams anymore, the documentation team are separated from the dev team. who are separated from the support team. With Outlook it is even worse, one team is busy ~~updating~~ wrecking the people/contacts facility, while another develops "new outlook for windows", while another writes a blog entry saying that some change is coming in the future and completely ignores all the comments stating that the proposed change is unwanted and will break the way people actually use the product.....
Nirmal Philips Tom 65 Reputation points

2026-09-02T11:14:34.0533333+00:00

@Technonath This is so true. Microsoft Support hasn't been particularly helpful with this so far, and it does feel like the initial support teams have limited visibility into what's happening.

The latest update I've received from Microsoft is that they're now engaging their internal Outlook engineering/product channels to verify whether this is a known issue or regression associated with the MC1458476 rollout. They've also said they'll provide an escalation or tracking reference if one becomes available.

So unfortunately, we're still waiting for a definitive answer from the Outlook product team.

Has anyone else received anything further from Microsoft — particularly a product-team confirmation, known issue/reference ID, engineering escalation, or confirmation on whether organisational branding is expected to return once the rollout is complete?
Scott Wichall 15 Reputation points

2026-09-03T15:50:31.62+00:00

@Nirmal Philips Tom I can confirm (after an application restart) that branding has returned to both New Outlook and OWA!

Answer recommended by moderator

Nirmal Philips Tom 65

Update – organisational branding has returned

The Microsoft 365 organisational branding has now returned for us in Outlook.

We did not make any changes to our tenant theme or Outlook configuration, so the restoration appears to have happened service-side.

Has anyone else who was affected seen their organisational branding return as well?

Jayden-P 2,600 Reputation points Independent Advisor

2026-09-03T16:28:27.8266667+00:00

I'm glad to hear that, it is back to normal for my tenant as well.
Yu Kai Lim 0 Reputation points

2026-09-04T02:04:51.8+00:00

Hi can confirm it showed up in my tenant as well without changing anything on my end.

4 additional answers

Your answer

Dan Cauchois 10 Reputation points

2026-08-26T10:37:38.62+00:00

We are seeing the exact same issue.
NolanSayCat 5 Reputation points

2026-08-27T10:01:35.5166667+00:00

So, can someone explain the point of allowing admins to define org themes via admin centre, if the new "experience" is being designed to completely ignore it??
Olivier Lagacé - VNET 5 Reputation points

2026-08-28T14:15:03.97+00:00

This is ridiculous. We’re an MSP, and many of our clients are calling us because they think they’ve been hacked. Using custom organizational colors is one of the things that helps users distinguish their legitimate tenant from a phishing site.

How could you take such a major step backward?
Nicholas Piasecki 6 Reputation points

2026-08-31T17:33:56.7966667+00:00

Restarted today and hit this. It worked for years and was very helpful to tell which tenant I was in. Considering the amount of other users who are experiencing the issue, it's safe to say that they broke it. Hopefully a Fortune 500 will eventually complain and it'll just magically fix itself one day.
Jayden Cameron 0 Reputation points

2026-09-02T07:34:42.3833333+00:00

Confirming the same issue in our CamCore tenant.

This worked normally until about a week ago, with no changes to our tenant theme. The default theme still has our organisation logo configured and “Prevent users from overriding their theme” enabled. SharePoint and OneDrive continue to show CamCore branding, but Outlook on the web now shows the standard blue Outlook header with no organisation logo.

The timing appears to align with MC1458476. In Outlook Settings → General → Appearance, the built-in/classic themes are present, but the locked organisation theme is not applied. Has Microsoft confirmed whether this rollout changes support for organisation themes in Outlook, and is there a fix or rollback ETA?
Technonath 10 Reputation points

2026-09-02T10:40:24.98+00:00

As per normal the usual lack of testing on the developers part and complete lack of any communication between the "support team" and the dev team. MS Support is a total joke, it is just a bunch of people working for an external company branded as MS Support and as soon as any ticket needs escalation to a dev they have no powers or channels to do this.

Don't expect an answer from the support team - it will never come.

Microsoft employees work in such small Silo's now with no communication between the teams anymore, the documentation team are separated from the dev team. who are separated from the support team. With Outlook it is even worse, one team is busy ~~updating~~ wrecking the people/contacts facility, while another develops "new outlook for windows", while another writes a blog entry saying that some change is coming in the future and completely ignores all the comments stating that the proposed change is unwanted and will break the way people actually use the product.....
Nirmal Philips Tom 65 Reputation points

2026-09-02T11:14:34.0533333+00:00

@Technonath This is so true. Microsoft Support hasn't been particularly helpful with this so far, and it does feel like the initial support teams have limited visibility into what's happening.

The latest update I've received from Microsoft is that they're now engaging their internal Outlook engineering/product channels to verify whether this is a known issue or regression associated with the MC1458476 rollout. They've also said they'll provide an escalation or tracking reference if one becomes available.

So unfortunately, we're still waiting for a definitive answer from the Outlook product team.

Has anyone else received anything further from Microsoft — particularly a product-team confirmation, known issue/reference ID, engineering escalation, or confirmation on whether organisational branding is expected to return once the rollout is complete?
Scott Wichall 15 Reputation points

2026-09-03T15:50:31.62+00:00

@Nirmal Philips Tom I can confirm (after an application restart) that branding has returned to both New Outlook and OWA!
Jayden-P 2,600 Reputation points Independent Advisor

2026-09-03T16:28:27.8266667+00:00

I'm glad to hear that, it is back to normal for my tenant as well.
Yu Kai Lim 0 Reputation points

2026-09-04T02:04:51.8+00:00

Hi can confirm it showed up in my tenant as well without changing anything on my end.

Answer 1

Hi @Nirmal Philips Tom

I did some testing and created a completely new Microsoft 365 organizational theme.

The new theme is applied successfully in both SharePoint and the Microsoft 365 Admin Center, including the updated banner/navigation color and branding. This suggests that the theme configuration itself is working correctly and that Microsoft 365 is processing the new theme as expected.

However, Outlook on the web and New Outlook for Windows do not reflect the change. They continue to show the default Outlook blue header and no organizational logo. The same as you described.

I also notice some other apps such as Form, Booking, etc. do not reflect the organization theme and logo as well.

Given that the updated theme is visible in SharePoint and the Admin Center but not in Outlook, this appears less likely to be a configuration issue and more likely to be something specific to how Outlook is behaving with Microsoft 365 organizational themes.

My recommendation is to open a support ticket with Microsoft support team. They will be able to investigate this issue further.

Answer 2

Lucien Buitenhuis 10

it's all due to this MC1458476 and our company doesn't like this...

MC1458476

Summary

Microsoft is introducing an optional setting in Outlook on the web and new Outlook for Windows to mimic classic Outlook’s look and feel. It helps users transitioning from classic Outlook by adjusting visual style and layout. The setting is off by default, can be toggled anytime, and rolls out globally from August to October 2026. No admin action is required.

What will happen

A new optional setting will be available in Outlook settings.
All users of Outlook on the web and the new Outlook for Windows will see the setting.
Most users will continue to see the standard new Outlook experience unless they choose to enable the setting.
Some users transitioning from classic Outlook to the new Outlook may have the setting enabled by default to provide a more familiar experience during the transition.
Users can enable or disable the setting at any time.
The setting affects only the individual user's visual Outlook experience.
The setting can be managed from Settings > General > Appearance.
This change does not modify mailbox data, permissions, organizational settings, or existing Outlook functionality.
This change does not affect or override administrator controls governing migration to or availability of the new Outlook.

Nirmal Philips Tom 65 Reputation points

2026-08-26T08:57:21.37+00:00

@Lucien Buitenhuis

Thanks for the information. MC1458476 does appear to line up with the timing and the affected Outlook experiences.

the new “Enable classic Outlook style” option referenced in MC1458476 is not yet available for us under Settings > General > Appearance, so we haven't been able to test whether disabling it restores the organisational branding.

We've now raised a support request with Microsoft

Do you currently have the new Classic Outlook style option available in your tenant? If so, does disabling it restore your organisation's branding?

@Scott Wichall @Jayden-P
Darren Share 10 Reputation points

2026-08-26T09:02:46.95+00:00

I noticed this issue a couple of days ago and guessed it was related to the upcoming layout changes. The timing was too much of a coincidence. We also don't have the classic theme option yet. @Nirmal Philips Tom Please let us know how your support query goes.
Jayden-P 2,600 Reputation points Independent Advisor

2026-08-26T09:06:39.0233333+00:00

The same for me, please let me know if you heard anything from the support team.
Scott Wichall 15 Reputation points

2026-08-26T09:12:58.0066667+00:00

@Nirmal Philips Tom we appear to have "Classic Themes" in the settings, however the checkbox to enable or disable it is not present as per the technote.

Answer 3

Scott Wichall 15

Can confirm that we have the same problem and will be opening a support case with MS about it.

As @Lucien Buitenhuis noted, it seems possible that MC1458476 could be related to this, there is now a "classic themes" section in web based Outlook and New Outlook, however, the checkbox to enable it or disable it as per the MS technote is not present.

We do not have any extra themes setup in Org settings, we long ago modified the default theme and its worked very well for years. Very irritating.

Jayden-P 2,600 Reputation points Independent Advisor

2026-08-26T08:23:55.83+00:00

Hi @Lucien Buitenhuis and @Scott Wichall

Thanks for sharing your situation.

I have reviewed MC1458476 and it did mention "This change does not modify mailbox data, permissions, organizational settings, or existing Outlook functionality.".

From my perspective, it's more likely of an unexpected behavior. If you have any news from the support team, please feel free to share here.

Answer 4

Response from Microsoft Support:

Based on our investigation, the behavior you are experiencing appears to be related to Microsoft's ongoing Outlook user experience rollout referenced in Message Center Notification MC1458476. This update introduces a new "Classic Outlook theme experience" for Outlook on the web and New Outlook for Windows and includes changes to the Outlook visual interface, such as header styling, layout, icons, and overall appearance.

We understand that your Microsoft 365 organizational theme is correctly configured and continues to display as expected in SharePoint. Since the issue is occurring across multiple users and in both Outlook on the web and New Outlook for Windows, it does not appear to be related to client configuration, device-specific settings, or the organizational theme setup itself.

At present, Microsoft is deploying this feature in phases. As part of the rollout, some tenants may experience changes in Outlook's appearance before the**"Enable classic Outlook style"** option becomes available under Settings > General > Appearance. Therefore, the absence of this setting for your users at this time can be expected during the staged deployment.

Based on currently available information, the following observations have been made:

Organizational branding remains visible in SharePoint and other Microsoft 365 services.

Outlook on the web and New Outlook for Windows may display the default Outlook blue header instead of the customized organizational navigation color.

The organizational logo may no longer be displayed within Outlook.

Similar behavior has been reported by other organizations during the rollout period. [[learn.microsoft.com]](https://gbr01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flearn.microsoft.com%2Fen-us%2Fanswers%2Fquestions%2F5985270%2Fmicrosoft-365-organisational-theme-no-longer-appli&data=05%7C02%7Cnirmal.tom%40sterlingstreet.co.uk%7C5773b2eb9c8d4e892e7908df0363503c%7Ce6872f078be3457d90d25010ffa49fdc%7C0%7C0%7C639233397244939068%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C4000%7C%7C%7C&sdata=8mS6myVr3z46GilE07C0TubxLyRcIqt3TDzHBuvWIq0%3D&reserved=0"Original URL: https://learn.microsoft.com/en-us/answers/questions/5985270/microsoft-365-organisational-theme-no-longer-appli. Click or tap if you trust this link.")

At this stage, there is no tenant-level configuration available to restore the previous Outlook branding experience, and the behavior appears to be associated with Microsoft's service-side updates. [[mc.merill.net]](https://gbr01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmc.merill.net%2Fmessage%2FMC1458476&data=05%7C02%7Cnirmal.tom%40sterlingstreet.co.uk%7C5773b2eb9c8d4e892e7908df0363503c%7Ce6872f078be3457d90d25010ffa49fdc%7C0%7C0%7C639233397244975379%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C4000%7C%7C%7C&sdata=rm08PcGi2Bi3DqRCPO5Qk3GQpCvedYUEh354DqL2sy8%3D&reserved=0"Original URL: https://mc.merill.net/message/MC1458476. Click or tap if you trust this link."), [[learn.microsoft.com]](https://gbr01.safelinks.protection.outlook.com/?url=https%3A%2F%2Flearn.microsoft.com%2Fen-us%2Fanswers%2Fquestions%2F5985270%2Fmicrosoft-365-organisational-theme-no-longer-appli&data=05%7C02%7Cnirmal.tom%40sterlingstreet.co.uk%7C5773b2eb9c8d4e892e7908df0363503c%7Ce6872f078be3457d90d25010ffa49fdc%7C0%7C0%7C639233397245003738%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C4000%7C%7C%7C&sdata=ENTaHKaT2HKHXxGVygCFJFIB4vOSDamz4Hq5UEZNO%2F0%3D&reserved=0"Original URL: https://learn.microsoft.com/en-us/answers/questions/5985270/microsoft-365-organisational-theme-no-longer-appli. Click or tap if you trust this link.")

We will continue to monitor Microsoft's guidance regarding this feature rollout. If Microsoft publishes any additional information or identifies this as a known issue requiring remediation, we will share those updates with you accordingly.

@Dan Cauchois @Darren Share @Jayden-P @Lucien Buitenhuis @Scott Wichall

Darren Share 10 Reputation points

2026-08-26T14:53:37.5566667+00:00

Thanks. Doesn’t read like the support wonks have actually flagged this as a bug with the developers but are just hoping someone notices and fixes it. Is that right? Or, most annoying possibility, it’s deliberate and they’ll remove it across the board at some point.
Jayden-P 2,600 Reputation points Independent Advisor

2026-08-26T15:46:10.79+00:00

Thanks for your information, I appreciate it.
Nirmal Philips Tom 65 Reputation points

2026-08-27T10:25:26.41+00:00

Microsoft Support could not currently confirm whether the loss of organisational branding is temporary or permanent, whether the branding will return after the rollout completes, or whether the new Classic Outlook style setting will have any effect on it.

They also confirmed that there is currently no announced tenant-level administrative control to restore/enforce the previous Outlook branding experience.

We have asked Microsoft Support to confirm whether our findings have been escalated to the relevant Outlook product/engineering team and whether this is being tracked internally as a known issue or regression.

I’ll update this discussion again when we receive further information from Microsoft.
Nirmal Philips Tom 65 Reputation points

2026-08-27T10:25:52.7466667+00:00

Microsoft Support could not currently confirm whether the loss of organisational branding is temporary or permanent, whether the branding will return after the rollout completes, or whether the new Classic Outlook style setting will have any effect on it.

They also confirmed that there is currently no announced tenant-level administrative control to restore/enforce the previous Outlook branding experience.

We have asked Microsoft Support to confirm whether our findings have been escalated to the relevant Outlook product/engineering team and whether this is being tracked internally as a known issue or regression.

I’ll update this discussion again when we receive further information from Microsoft.