Windows 10 Mail had at least two separately reported interface tests: a late-2018 Fluent Design and layout experiment for some Skip Ahead Insiders, followed by a January 2019 test of account navigation and dark message display for Fast ring Insiders. These were limited Insider tests, not evidence that every user received the same redesign or that the old Mail app is currently getting that interface.
What changed in the Windows 10 Mail app?
The reports describe two different experiments, with different audiences and different interface changes. Windows Central covered both; they should not be treated as one combined update.
| Report | Insider audience and timing | Reported changes | What the report establishes |
|---|---|---|---|
| Fluent Design and layout | Small group in Skip Ahead; November 20, 2018 | Fluent Design reveal effects, a window without the usual separate titlebar, and a redesigned email list | Windows Central described it as an apparent A/B test. The reporter had Mail and Calendar version 8700.40315 but did not see the new design on their own system, indicating selective availability. Windows Central’s November 2018 report. |
| Account navigation and dark message display | Fast ring; January 24, 2019 | Email accounts visible in the left sidebar when the hamburger menu was collapsed; message display followed the system light or dark theme, with an in-message toggle to switch themes | Windows Central said the update appeared to be rolling out to Fast ring Insiders. Its expectation that it might reach more users with the then-upcoming 19H1 update was a forecast, not confirmation of the eventual rollout. Windows Central’s January 2019 report. |
Why did some users see a different Mail interface?
Insider features can be tested with only a subset of participants, and an app version alone did not guarantee that the revised design was enabled. In the November 2018 report, the reporter had the cited app version but could not see the new layout on their own system. The January 2019 report concerned a separate test in the Fast ring, not the Skip Ahead experiment.
That distinction matters when interpreting screenshots or accounts from other users: different people could be on different rings, or the change could be enabled selectively within a ring. Neither report establishes that all Windows 10 users received either interface.
Do these 3 things before closing this tab:
1Repair Windows errors before they cause bigger problems2Fix the driver behind crashes, sound loss and screen glitches3Clear out junk files and repair common Windows errors#1 Best Overall
Were these changes released to everyone?
The reports establish that the designs were being tested, not that either exact interface became a universal consumer release. Windows Central’s January 2019 expectation of a broader release alongside Windows 10 version 19H1 should remain an expectation made at the time; the report does not verify that outcome.
Microsoft’s later Insider announcements also caution against treating a test build as a release promise. In its July 1, 2020 announcement for Build 20161, Microsoft said, “First—as a reminder, these builds are from our Active Development Branch and are not tied to any upcoming Windows 10 release.” The announcement also noted that some build features initially went only to a subset of Dev Channel Insiders. Microsoft’s Build 20161 announcement.
Rank #2
- 15.6" diagonal, HD (1366 x 768), micro-edge, BrightView, 220 nits, 45% NTSC.
How does the 2020 icon redesign fit in?
Microsoft documented redesigned icons for the built-in Mail and Calendar apps as starting to roll out earlier in 2020. That is useful context for later visual changes, but it is distinct from the 2018 Fluent Design/layout test and the January 2019 account and message-theme test. The icon announcement does not verify that every detail from those earlier reports became standard. Microsoft’s 2020 announcement.
Is the old Windows Mail app becoming Outlook?
Microsoft Support’s current getting-started guidance says eligible Windows Mail and Calendar users on Windows 10 and Windows 11 may see a Try the new Outlook toggle. The support listing identifies Microsoft work or school accounts and Outlook.com, Hotmail, or Gmail accounts among the supported account types. Eligibility and availability can change, so consult Microsoft’s current new Outlook guidance for the latest details. This present-day transition is separate from the historical Insider interface experiments described above.
Rank #3
- 10th Generation Intel Core i5-1035G1 processor
- 12GB system memory for full-power multitasking
- 256GB Solid State Drive
- 15.6" Micro-edge touchscreen display
A separate earlier example of Mail Insider testing
Mail had other Insider experiments before the 2018–2019 interface reports. Microsoft’s October 25, 2016 notes for Build 14955 documented Outlook Mail and Calendar version 17.7466.4062x.0, including opening messages in a new window, Quick Actions from new-email notifications, and @mentions. Those features illustrate the app’s ongoing iteration but are not part of the later visual tests. Microsoft’s Build 14955 notes.
Quick Recap
Best Value
Rank #4
- Latitude 7480 Laptop 14"
- Intel Core i7 6th Gen i7-6600U -Core Processor 2.6GHz (3.4GHz With Turbo Boost)
- 256 GB SSD Hard Drive & 16GB Memory
- 1920x1080 FHD resolution Non-Touch with Webcam and an integrated graphics chip
- Wireless Wifi & Bluetooth
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
